WAEC SSCE - Computer Studies - 2022

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Serial files are stored as they come, meaning that the records are simply added to the end of the file as they are created or received. A serial file is a type of file organization used in computer systems where records are stored one after the other, with no particular order or sequence. The records are simply appended to the end of the file as they are created or received, and there is no attempt to sort or organize them in any particular way. Serial files are commonly used for logging or recording sequential events such as sensor readings, financial transactions, or web server requests. They are simple and easy to implement and are suitable for applications where the records are read in the order they were created. However, one drawback of serial files is that searching and sorting records can be time-consuming and inefficient because the records are not stored in any particular order. For applications that require frequent searching or sorting of records, other file organization methods such as indexed files or relational databases may be more appropriate. Therefore, the correct answer to the question is that serial files are stored as they come, with no particular order or sequence.

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The keyboard key combination ALT + F4 in Microsoft Windows will close active programs. When you press ALT + F4, it sends a command to the operating system to close the currently active program or window. This is a quick way to exit a program when you're finished using it, rather than using the mouse to click on the "X" button at the top right corner of the window.

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The exception in the given guidelines for drawing flowcharts is that it should follow a direction of right to left or bottom to top. The standard practice for drawing flowcharts is to follow a logical direction of left to right or top to bottom. This ensures that the flowchart is easy to read and understand. Flowcharts should also have a clear and logical start and finish, and should be neat, organized, and easy to follow.

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One-millionth of a second is also referred to as a "microsecond." The prefix "micro-" means "one millionth," so a microsecond is one millionth of a second. It is commonly used to measure small intervals of time in electronics, computer science, and other fields where precise timing is important. For example, the time it takes for a computer's processor to execute a single instruction is typically measured in microseconds.

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In the URL https://waec.org.ng, the domain name is "waec.org.ng". A domain name is a unique name that identifies a website on the internet. It is part of a larger internet address called a URL (Uniform Resource Locator), which specifies the exact location of a web page or resource on the internet. In the given URL, "waec.org.ng" is the domain name. The ".org.ng" is the top-level domain (TLD) for Nigeria, and it indicates that the website is operated by an organization based in Nigeria. The "https://" portion of the URL specifies the protocol being used to access the website, which in this case is HTTP Secure, or HTTPS. The "www" portion is a subdomain that is used to indicate the specific server that hosts the website. However, many websites nowadays omit the "www" subdomain and simply use the domain name. Therefore, the correct answer to the question is "waec.org.ng" is the domain name in the given URL.

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In a typical compiler interface diagram, the part labelled Y represents the output of the compilation process. This output is usually in the form of machine-readable instructions that can be executed directly by a computer's processor. The specific type of output produced by the compiler depends on the programming language being used and the target machine's architecture. It could be in the form of assembly code, object code, or executable binary code. Therefore, the correct option is: object code or binary code, depending on the level of abstraction of the compilation process. However, if the diagram is showing the output after the optimization phase, then it could also be intermediate code.

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One similarity between bespoke software and application packages is that they are both meant to be used by computer end users. Bespoke software refers to custom-made software that is developed for a specific user or organization to meet their unique requirements. It is often designed and developed by professional software developers in consultation with the client. On the other hand, application packages or software packages are pre-written software programs that are designed to perform a specific set of functions and are available to the general public. These packages are developed by software companies to address the needs of a wide range of users. Despite the fact that bespoke software is custom-made and application packages are pre-written, both types of software are intended to be used by computer end-users. The purpose of both bespoke software and application packages is to provide users with software solutions that can help them perform specific tasks or solve specific problems. Therefore, the correct answer to the question is that both bespoke software and application packages are meant to be used by computer end users.

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A laptop computer would be the most suitable type of computer for a student who lives in a remote village without constant electricity. This is because a laptop is portable and can be easily charged using a battery or solar-powered charger, allowing the student to work even in areas with limited or no access to electricity. Additionally, a laptop can perform all the necessary functions required for studying, including research, writing, and online communication. In contrast, a desktop computer requires a constant source of electricity and is not portable, making it less practical for a student living in a remote area without a reliable source of power. Mainframe and minicomputers are not suitable for individual use, as they are typically used in large organizations and require specialized expertise to operate.

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In number system, base 16 is called "hexadecimal". We use different number systems in our daily lives to represent and manipulate numbers. The most common number system is the decimal system, which uses ten digits (0, 1, 2, 3, 4, 5, 6, 7, 8, 9) to represent all numbers. However, in some computer science and engineering applications, it is more convenient to use the hexadecimal number system, which uses 16 digits (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F) to represent numbers. The letters A through F are used to represent the numbers 10 through 15, respectively. For example, the decimal number 15 is represented as F in hexadecimal, and the decimal number 255 is represented as FF in hexadecimal. So, to summarize, base 16 is called "hexadecimal" because it uses 16 digits to represent numbers, and it is commonly used in computer science and engineering applications.

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All of the options listed are used to run a slide show in MS PowerPoint except for "choosing the slide show tab". The "slide show tab" is used to access and customize slide show settings, but it does not actually start the slide show. The other options listed are used to start the slide show: pressing F5 starts the slide show from the beginning, pressing shift + F5 starts the slide show from the current slide, and clicking on the slide show icon bar also starts the slide show from the beginning.

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The logic gate in the given diagram is an AND gate. An AND gate is a digital logic gate that has two or more inputs and produces an output that is the logical conjunction of the inputs. In an AND gate, the output is only HIGH when both the inputs are HIGH. In the given diagram, the two inputs are A and B, and the output is Y. Therefore, if A and B are both HIGH, then the output Y will be HIGH, otherwise, it will be LOW.

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Compared to earlier computers, modern computers are faster and smaller. This means that they can process information at a much faster rate than earlier computers and they are also more compact and easier to transport. Additionally, modern computers have more storage capacity, enabling them to store larger amounts of data. This has made them more efficient and user-friendly, making them an indispensable tool for both personal and professional use.

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The program that is loaded into a special area on a microprocessor or ROM on a one-time basis and becomes part of the hardware is called firmware. Firmware is a specific type of software that is embedded into hardware devices, such as microprocessors or other electronic components, to perform a specific function. Firmware is designed to be permanent and cannot be easily modified or updated like other software programs. It is often used in devices like routers, printers, and digital cameras, where it provides low-level control of the hardware and ensures that the device functions correctly.

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Deleted items in computers are temporarily stored in the recycle bin. When you delete a file or folder on your computer, it is not permanently removed from your system. Instead, it is moved to the recycle bin, which acts as a holding area for deleted files. The recycle bin is a temporary storage location that allows you to retrieve files that were deleted by mistake or that you no longer need. Once you empty the recycle bin, the files are permanently deleted from your computer's memory unit. Therefore, the recycle bin serves as a safety net for deleted items and helps prevent accidental file loss.

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The correct answer is "payroll system". The other options - Corel Draw, MS Software, and MS Word - are all examples of general purpose application software. These are software programs that are designed to be used for a wide variety of tasks, such as creating documents, editing images, or managing data. A payroll system, on the other hand, is a specialized application software that is designed specifically for managing payroll processes, such as calculating employee salaries, taxes, and benefits. Therefore, it is not considered a general purpose application software.

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The correct answer is "I and II only". Booting refers to the process of starting up a computer system. During this process, the computer goes through several stages before the operating system is loaded and the user can begin using the computer. The first stage of booting is the Power on Self Test (POST), which checks the hardware components of the computer to make sure they are functioning properly. If any issues are detected during the POST, an error message will be displayed. The second stage of booting is the loading of the operating system. Once the hardware checks are completed, the computer loads the operating system from the hard drive or another storage device. Options III and IV are not stages of the booting process. Loading of emails is a task performed by an email client after the operating system has loaded, and starting in safe mode is an option that can be selected during the booting process to troubleshoot issues with the operating system.

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The key skills of a system analyst include the ability to troubleshoot, an interest in learning new skills, and proficiency in programming languages. However, motivational skills are not typically considered a key skill of a system analyst. System analysts are responsible for analyzing an organization's computer systems and procedures, designing information systems solutions to help the organization operate more efficiently and effectively, and ensuring that these solutions meet the organization's needs. The ability to troubleshoot problems and proficiency in programming languages are essential for this role, while an interest in learning new skills is important for keeping up with emerging technologies and trends in the field. Motivational skills, while important for many roles, are not typically considered a key skill for a system analyst.

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To determine the number of binary digits contained in 10MB of a memory stick, we need to know the size of a binary digit in a memory stick. One byte consists of 8 bits. Therefore, 10MB of memory consists of: 10 x 1024 x 1024 bytes To calculate the number of binary digits, we need to multiply the number of bytes by 8: 10 x 1024 x 1024 x 8 = 83,886,080 bits Therefore, 10MB of memory stick contains 83,886,080 binary digits. In summary, the answer is "10 x 1024 x 1024 x 8" which represents the total number of bits contained in 10MB of a memory stick.

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The shortcut key for the open dialog box in MS Word is "Ctrl + F12". When you press the "Ctrl + F12" keys simultaneously in MS Word, it opens the "Open" dialog box. This dialog box allows you to browse and select a file that you want to open in MS Word. The "Alt + F12" shortcut key in MS Word is used to save a document with a new name, while "F12" is used to open the "Save As" dialog box. The "Shift + F12" shortcut key is used to save the current document. Shortcut keys are a useful way to save time and increase productivity when working in MS Word. By learning and using shortcut keys, you can perform common tasks quickly and easily, without having to navigate through multiple menus and options.

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The maximum length of a text field in MS Access is 255 characters. This means that you can store up to 255 characters of text in a single field in a table. To put it simply, imagine that you have a field in a table that is used to store people's names. The maximum length of that field would be 255 characters, which is enough to accommodate even the longest names in the world (e.g., "Adolph Blaine Charles David Earl Frederick Gerald Hubert Irvin John Kenneth Lloyd Martin Nero Oliver Paul Quincy Randolph Sherman Thomas Uncas Victor William Xerxes Yancy Zeus"). If you try to enter more than 255 characters into a text field, Access will truncate the data and only store the first 255 characters. Therefore, it's important to make sure that the maximum length of your text fields is set appropriately based on the type of data you will be storing in them.

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The protocol used for email transmission is SMTP (Simple Mail Transfer Protocol). SMTP is a communication protocol for sending and receiving email messages over the internet. It is responsible for the transfer of email messages from one server to another until they reach the recipient's email server. SMTP is used to authenticate and encrypt email transmissions to ensure that they are secure and delivered to the intended recipient.

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To evaluate the expression, we need to follow the rules of arithmetic operations, which are Parentheses, Exponents, Multiplication and Division, and Addition and Subtraction (PEMDAS). First, we calculate 4^2, which is 16. Then, we perform multiplication and division from left to right, giving us: 2*6 + 2/4 * 2 * 16 = 12 + 0.5 * 32 = 12 + 16 = 28 Therefore, the result of the expression is 28. Hence, the correct option is "28".

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The example of information that does not fit with the other options is "plain shape of a rectangle". This is because the other options all relate specifically to measurements or calculations related to geometric shapes, while "plain shape of a rectangle" is a more general description that doesn't provide any specific information or calculation. For example, the "area of a circle" refers to the amount of space inside a circle, while the "circumference of a circle" refers to the distance around the outside of a circle. Similarly, the "perimeter of a rectangle" refers to the distance around the outside of a rectangle. In contrast, the phrase "plain shape of a rectangle" simply describes the fact that a rectangle is a four-sided shape with opposite sides that are equal in length and parallel to each other. It doesn't provide any specific information or calculation related to the rectangle, which is why it is the odd one out in this list of examples.

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EDSAC was produced using a concept known as "Stored program". The stored program concept is a fundamental idea in computer science that refers to the ability of a computer to store instructions in memory along with data. This allows the computer to retrieve and execute those instructions at a later time, without the need for human intervention. Before the advent of the stored program concept, computers were programmed using hard-wired circuitry, which made them inflexible and difficult to reprogram. However, with the stored program concept, computers became much more versatile and easier to program, leading to the development of more sophisticated software and the modern computing era. EDSAC, which stands for Electronic Delay Storage Automatic Calculator, was one of the first computers to be built using the stored program concept. It was designed and built in the late 1940s and early 1950s at the University of Cambridge, and was used for scientific research and engineering calculations. Therefore, the correct answer to the question is "Stored program".

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The numbers 10, 20, 30, 40, 50, 60, and 70 in the QBASIC program represent line numbers. In QBASIC, each line of code is identified by a line number. The line numbers are used to help navigate the program, jump to specific lines, and edit the code. In the example program, line 10 is a comment that describes the program, line 20 clears the screen, line 30 asks the user for input of the value of A, line 40 asks the user for input of the value of B, line 50 multiplies A and B and stores the result in the variable PRODUCT, line 60 prints the value of PRODUCT, and line 70 ends the program.

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a. An output device is a hardware component of a computer system that displays or prints the results or output of a computer's processing or data manipulation. b. The two types of printers are: - Impact printers: These printers produce printed characters or images by striking an inked ribbon against paper. Examples include dot-matrix printers. - Non-impact printers: These printers produce printed characters or images without striking the paper. Examples include inkjet printers and laser printers. c. i. A truth table for an AND gate with two input signals is as follows: | Input 1 | Input 2 | Output | |---------|---------|--------| | 0 | 0 | 0 | | 0 | 1 | 0 | | 1 | 0 | 0 | | 1 | 1 | 1 | ii. The output of an OR gate with the signals 0 and 1 is 1. An OR gate produces a logic 1 output when either or both of its input signals are 1. d. Two types of logic gates that give an output of 1 when all of its input signals are 1 are: - AND gate: An AND gate produces a logic 1 output only when all of its input signals are 1. - NAND gate: A NAND gate is the opposite of an AND gate, and produces a logic 0 output only when all of its input signals are 1. However, by adding an inverter to the output of an AND gate, a NAND gate can be created.

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To create a presentation on the topic of computer systems using Microsoft PowerPoint, follow these steps: 1. Open Microsoft PowerPoint. 2. Select the "Blank Presentation" option to start with a new presentation. 3. Slide (a): - Choose the "Title Slide" layout from the "Layout" options. - In the title text box, type "Computer Systems." - Select the title text and choose the font type "Arial Black" with a size of 44 points. 4. Slide (b): - Insert a new slide using the "New Slide" option or by pressing Ctrl+M. - Choose the "Title and Content" layout from the "Layout" options. - In the title text box, type "Definition of computer." - Select the title text and choose the font type "Algerian" with a size of 40 points. - In the content text box, type the following passage: "A computer is a device that accepts information in the form of digitized data and manipulates it for some results based on a program or sequence of instructions on how the data is to be processed." - Select the content text and choose the font type "Times New Roman" with a size of 30 points. 5. Slide (c): - Insert a new slide. - Choose the "Title and Content" layout. - In the title text box, type "CLASSIFICATION OF COMPUTERS." - Select the title text and use the same font type and size as in slide (b). - In the content text box, type the following points: - By type - By Size - By Purpose - By Generation - Select the content text and use the same font type and size as in slide (b). 6. Slide (d): - Insert a new slide. - Choose the "Title and Content" layout. - In the title text box, type "CLASSIFICATION BY TYPE." - Select the title text and use the same font type and size as in slide (b). - In the content text box, type the following bullet list: - Digital Computer - Analogue Computer - Hybrid Computer - Select the content text and use the same font type and size as in slide (b). 7. Slide (e): - Insert a new slide. - Choose the "Title and Content" layout. - In the title text box, type "CLASSIFICATION BY GENERATION." - Select the title text and use the same font type and size as in slide (b). - In the content text box, type the following list: - First Generation (e.g., UNIVAC) - Second Generation (e.g., HAVARD MARKII) - Third Generation (e.g., IBM 360) - Fourth Generation (e.g., Microcomputer) - Select the content text and use the same font type and size as in slide (b). 8. Slide (g): - Go to the "Insert" tab and click on "Footer" in the "Text" section. - In the Footer dialog box, enter your full name and index number. - Choose a font size of 14 points and make the text bold. - Click "Apply to All" to add the footer to all slides. 9. Save your work in a folder on the desktop using your full name as the file name. - Go to the "File" tab and select "Save As." - Choose the desired location and enter your full name as the file name. - Click "Save" to save the presentation. 10. To print your work and submit

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(a) i. Star topology: In a star topology, all the devices are connected to a central device called a hub or switch. The hub acts as a central point of communication and manages the flow of data between devices. Here is a labeled diagram of a star topology: ``` Device 1 Device 2 Device 3 | | | +-------------+-------------+ Hub | CPU ``` ii. Bus topology: In a bus topology, all the devices are connected to a single cable called a bus. The data transmitted by one device is received by all the devices on the network. Here is a labeled diagram of a bus topology: ``` Device 1 | Device 2 | Device 3 | +-------+ | Bus | +-------+ | CPU ``` iii. Ring topology: In a ring topology, all the devices are connected to form a closed loop. Data is transmitted in one direction around the ring, and each device acts as a repeater to amplify the signal and pass it on to the next device. Here is a labeled diagram of a ring topology: ``` +-----------+ | Device 1 | +-----------+ | +-----------+ | Device 2 | +-----------+ | +-----------+ | Device 3 | +-----------+ | +-----------+ | CPU | +-----------+ ``` (b) i. Advantage of Star topology: One advantage of a star topology is that it is easy to install and maintain. If a device fails or needs to be added, it can be easily replaced or added without affecting the rest of the network. Additionally, the hub or switch can be used to monitor and manage the network traffic, making it easier to troubleshoot any issues. ii. Advantage of Bus topology: One advantage of a bus topology is that it is relatively inexpensive to install and maintain. Since all the devices are connected to a single cable, it requires less cable and equipment than other topologies. Additionally, the bus topology is scalable, meaning new devices can be added to the network without significant disruption. (c) i. Disadvantage of Bus topology: One disadvantage of a bus topology is that it is vulnerable to network congestion and collisions. Since all the devices share a single communication channel, if multiple devices try to transmit data simultaneously, collisions can occur, causing delays and reducing the network performance. Additionally, if the bus cable fails, the entire network can be affected. ii. Disadvantage of Ring topology: One disadvantage of a ring topology is that it is also vulnerable to network congestion and failures. If a device or cable fails, the entire network can be disrupted. Additionally, adding or removing devices from a ring topology can be challenging and require significant network reconfiguration.

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To prepare the First Quarter Sales Worksheet for Summer Break Travels Inc., we need to perform the following steps:

a) Calculate the total sales at each marketing outlet and the amount of money made for each vacation place: To calculate the total sales at each marketing outlet, we need to add up the sales from all the four methods (mail, campus, telephone, and internet) for each vacation place. Similarly, to calculate the amount of money made for each vacation place, we need to add up the sales from all the four methods for each location. We can use the SUM function in Excel to calculate these totals. Here's how the table will look after calculating the totals:

b) Format the table as follows: - Bold and uppercase the title: "SUMMER BREAK TRAVELS, INC. FIRST QUARTER SALES" - Fill the table with a white background of 1 darker-25"

c) Create two charts:

- Pie chart: To create a pie chart, we need to select the sales data for each marketing outlet (i.e., mail, campus, telephone, and internet) and insert a pie chart from the "Insert" tab. We can then format the chart by adding data labels and a legend to show which method is most effective.

- Bar chart: To create a bar chart, we need to select the sales data for each vacation place and insert a bar chart from the "Insert" tab. We can then format the chart by adding axis labels and a title to show which vacation place is the most popular.

d) Type in the formula used in calculating total for each location below your table (enclosed in ""): For example, the formula used to calculate the total sales for Bar Beach is "=SUM(B2:E2)".

e) Save, print out your work, and submit to the supervisor. In summary, the First Quarter Sales Worksheet for Summer Break Travels Inc. involves calculating the total sales at each marketing outlet and the amount of money made for each vacation place using Excel's SUM function, formatting the table with a bold and uppercase title and a white background, creating a pie chart and a bar chart to visualize the sales data, and typing in the formulas used to calculate the totals. The final output should be saved, printed out, and submitted to the supervisor.

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Here's a simple QBASIC program that accepts a word from the keyboard and checks if it is a palindrome or not: ``` CLS INPUT "Enter a word: ", word$ n = LEN(word$) FOR i = 1 TO n / 2 IF MID$(word$, i, 1) <> MID$(word$, n - i + 1, 1) THEN PRINT word$; " is not a palindrome" END END IF NEXT PRINT word$; " is a palindrome" ``` Explanation: - `CLS` clears the screen before the program runs. - `INPUT` prompts the user to enter a word and stores it in the variable `word$`. - `n = LEN(word$)` gets the length of the word and stores it in the variable `n`. - The `FOR` loop checks each character of the word from the beginning to the middle of the word (i.e., `n/2`). If a character does not match its corresponding character from the end of the word, then the program prints a message saying that the word is not a palindrome and ends the program. - If the loop finishes without finding any mismatch, then the program prints a message saying that the word is a palindrome.

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(a) The actions that will ensure that the files are kept confidential and secured are: - Use of folder - Use of password - Use of biometrics (if available) (b) Two disadvantages of computer files as compared to manual files are: - Computer files are vulnerable to hacking, viruses, and other security threats. - If a computer crashes or there is a power outage, the files may be lost or corrupted. (c) (i) In Microsoft Excel, charts refer to graphical representations of data. They are used to visually display data in a way that makes it easier to understand and analyze. (ii) Two types of charts in Microsoft Excel are: - Column chart: This type of chart displays data as vertical columns. It is useful for comparing values across different categories or time periods. - Pie chart: This type of chart displays data as slices of a circle. It is useful for showing the proportion of different values in a dataset.

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a) i) The slide master in PowerPoint is a feature that allows users to customize and format the layout and design of slides in a presentation. By editing the slide master, users can create a consistent and professional look throughout their presentation, with changes made to the master applying to all slides in the presentation. ii) To rename the slide master in MS PowerPoint, follow these steps: 1. Open the PowerPoint presentation containing the slide master you wish to rename. 2. Click on the "View" tab in the PowerPoint ribbon. 3. Click on "Slide Master" to open the slide master view. 4. In the left-hand pane, right-click on the slide master you wish to rename. 5. Select "Rename Master" from the drop-down menu. 6. Type in the new name for the slide master and press enter. b) i) The handout master in PowerPoint is a feature that allows users to customize the layout and design of handouts that are printed or distributed to audience members. By editing the handout master, users can add logos, headers, footers, page numbers, and other elements to create a professional-looking handout. ii) The notes master in PowerPoint is a feature that allows users to customize the layout and design of speaker notes that accompany each slide. By editing the notes master, users can add logos, headers, footers, and other elements to create a consistent and professional look for their speaker notes. Additionally, users can format the font, color, and size of the speaker notes text to enhance readability during a presentation.

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This question is asking you to create a database with a table called "customers" and define the fields appropriately with the "Custom ID" as the primary key. Then, you need to create a form from the "customers" table and save it as "REFORM". After that, you will enter ten records of your choice using the form. Next, you will write a query to retrieve the "First Name" and "Telephone" fields from the "customers" table. You will then use the retrieved data to design a report. Finally, you will insert a footer into the report and type in your full name.

In summary, this question is testing your knowledge of database creation, table design, form creation, query writing, report designing, and footer insertion. It is important to pay attention to the details and follow the instructions carefully to successfully complete this task.