WAEC SSCE - Data Processing - 2021

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A primary key is a field in a database that uniquely identifies each record. It acts as a unique identifier for each record in a table and ensures that no two records are the same. The primary key is used to connect related information stored in different tables in a database, and is essential for ensuring the accuracy and integrity of the data stored in a database. Simply put, it's like a fingerprint for each record in a table that helps distinguish it from other records.

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The formula to calculate the average of a given range of data from cell B2 to cell D4 in a Microsoft Excel worksheet is "=AVERAGE(B2:D4)". This formula uses the "AVERAGE" function in Excel, which calculates the average of a range of values. The range of values is specified by the parameters inside the parentheses, which in this case are "B2:D4". The colon (:) between B2 and D4 indicates that the range includes all the cells between and including B2 and D4. By using this formula, Excel will calculate the average of all the values within the specified range and display the result in the cell where the formula is entered.

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A file organization that requires a primary key is the Indexed file organization. In this type of file organization, records are stored in an index, which is a separate data structure that allows for fast access to the records based on the value of the primary key. The primary key is a unique identifier for each record, and it is used to look up the record in the index. This allows for efficient and quick retrieval of records, which is important in many applications. So, having a primary key is essential in indexed file organization.

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The term "Single server" is not a feature of a distributed database. A distributed database is a database that is spread across multiple servers or nodes, with each node having its own portion of data. This allows for greater scalability and improved performance, as well as increased availability and reliability in the event of a single node failure. In contrast, a single server database is stored on a single, centralized server and does not have the benefits of a distributed database.

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A multi-user operating system is one that allows multiple users to access the same data at the same time. This type of OS enables different users to log into the system and access files, folders, and programs that are shared across the network. Each user can have their own account with individual permissions, which controls what they can and can't access. For example, in a multi-user operating system, a user can save a file on a shared folder, and other users can access and modify that file if they have permission. This allows multiple users to collaborate and work together on the same documents, databases, or projects. In contrast, a single-user operating system only allows one user to access the data at a time, while a multi-tasking operating system allows one user to run multiple programs simultaneously. Virtual memory is a technology that allows the computer to use a portion of the hard drive as additional RAM, enabling the computer to run more programs than it could with physical RAM alone.

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To prevent the loss of data in a computer, it is better to implement a "backup" system. A backup is a copy of important data that can be used to restore the original data in case it is lost or damaged. By regularly backing up your data, you can protect against accidental deletion, hardware failure, viruses, and other potential risks that could cause data loss. There are various methods for backing up data, such as using an external hard drive, cloud storage services, or specialized backup software. It is important to make sure that backups are done regularly and stored securely in a different location from the original data to ensure that they are accessible and not affected by the same risks that could affect the original data.

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The malware which is programmed to initiate at a specific date or when a specific event occurs is called a "logic bomb". A logic bomb is a type of malware that is intentionally inserted into a system or software application by a malicious actor with the intention of causing damage or disruption at a predetermined time or when a specific trigger event occurs. A logic bomb is similar to a time bomb in that it is designed to lie dormant until a specific date or event occurs, at which point it is triggered to execute its malicious code. For example, a logic bomb could be programmed to erase critical files or data from a system on a certain date or when a particular employee's username is deleted from the system. Unlike other types of malware, a logic bomb may not necessarily be designed to spread or replicate itself to other systems. Instead, its sole purpose is to cause damage or disruption to the targeted system at a specific time or under certain circumstances.

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The statement "Data leads to information and information leads to knowledge" is true. Data refers to raw facts and figures, and can come from a variety of sources such as experiments, surveys, and observations. Information is created when data is processed, organized, and analyzed in a way that gives it meaning. This information can then be used to answer questions, make decisions, or solve problems. Knowledge is an understanding and awareness of information that has been acquired through experience and education. It's the ability to apply information to different situations and make informed decisions. So, data is the starting point, which is processed to create information, and that information is then used to build knowledge.

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To convert the binary number 101100101 to decimal (denary), we can use the positional notation system. Each digit in a binary number represents a power of 2, starting from the rightmost digit with 2^0, then increasing by a power of 2 for each subsequent digit (i.e., 2^1, 2^2, 2^3, etc.). Starting from the rightmost digit in 101100101, we have: 1 × 2^0 = 1 0 × 2^1 = 0 1 × 2^2 = 4 0 × 2^3 = 0 0 × 2^4 = 0 1 × 2^5 = 32 1 × 2^6 = 64 0 × 2^7 = 0 1 × 2^8 = 256 Adding up the results, we get: 1 + 0 + 4 + 0 + 0 + 32 + 64 + 0 + 256 = 357 Therefore, the decimal (denary) equivalent of the binary number 101100101 is 357.

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The joystick is mainly used for playing computer games. A joystick is a handheld device that allows users to control the movement of an object on a screen, such as a character in a game. The joystick usually has a stick that can be moved in different directions and buttons that can be pressed to perform different actions. Joysticks are popular among gamers because they provide a more immersive and intuitive way to interact with games than using a keyboard or mouse. While joysticks can also be used for other purposes, such as controlling airplanes or robotics, their primary use is for gaming.

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The manipulation of digitalized information by a computer or other electronic equipment is known as "data manipulation." This refers to the process of changing, organizing, or analyzing data using computer software or hardware. Data manipulation can involve a wide range of activities, such as sorting, filtering, merging, transforming, or calculating data in order to produce meaningful information or insights. For example, data manipulation might involve sorting a list of customer names alphabetically, calculating the average sales revenue for a particular product, or merging two databases to create a more comprehensive view of a business. Overall, data manipulation is an essential part of information processing, which involves the collection, organization, analysis, and communication of data. By manipulating digital information using computer technology, organizations can better understand and utilize their data, which can lead to improved decision-making and better business outcomes.

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A digital computer is the type of computer that counts in discrete form only. This means that it operates using a series of binary digits, or "bits," which can represent either a zero or a one. These bits are combined to form numbers, letters, and other symbols that can be processed by the computer. Digital computers are designed to perform specific tasks by following a set of instructions, or a "program." They are used in a wide range of applications, from simple calculations to complex simulations and data analysis. Digital computers are generally considered to be more accurate, reliable, and versatile than analog computers, which represent information in a continuous form.

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The term "Adobe PageMaker" is not typically included in web design packages. Web design packages typically include software tools for designing, creating, and publishing websites. Macromedia Dreamweaver, iWeb, and Front Page are all examples of web design software that are commonly used for this purpose. Adobe PageMaker, on the other hand, is a desktop publishing software that is used for creating printed materials such as brochures, flyers, and magazines. It is not specifically designed for web design and does not have the features and functionality needed for creating and publishing websites.

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When information is conveyed from one space to another, it is referred to as "transmission." Transmission refers to the process of sending data or information from one location to another through a communication channel, such as a wired or wireless network, cable, or satellite. This process involves encoding the information into a form that can be transmitted, sending it through the communication channel, and then decoding it back into its original form at the destination. Examples of transmission include sending an email, making a phone call, or streaming a video over the internet.

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The part labeled "I" in the CorelDraw tool bar is used to select objects. In CorelDraw and other graphic design software, the selection tool is used to select and manipulate objects within the design. This is an essential tool for making edits and changes to the design, as it allows you to select objects and move, resize, or modify them as needed. When you click on an object in the design with the selection tool, the object will become surrounded by selection handles, which indicate that the object is selected and can be edited. Additionally, the selection tool can be used to select multiple objects at once, making it easy to manipulate multiple elements in the design at the same time. It is important to note that the selection tool is just one of many tools available in CorelDraw and other graphic design software, and each tool has a specific purpose and function. Understanding the different tools and their uses is an important part of working with graphic design software.

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The protocol for transferring files from one machine to another is FTP (File Transfer Protocol). FTP is a standard network protocol used to transfer files from one host to another over a TCP-based network, such as the Internet. It is often used to upload or download files to or from a server, such as a web server or a file server. When using FTP, you typically connect to a server using a client software, such as FileZilla or WinSCP. Then, you can browse the server's file system, select the files you want to transfer, and either upload or download them. FTP is one of the oldest and most widely used file transfer protocols, and it is still widely used today due to its simplicity and versatility. However, it is important to note that FTP transfers are not secure, and it is recommended to use a secure file transfer protocol, such as SFTP (Secure File Transfer Protocol), if security is a concern.

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The media are channels or platforms that are used to transmit information from one person or group to another. Out of the options provided, a diary is not a medium for information transmission. A diary is a personal journal where individuals record their thoughts, feelings, experiences, and events that happen in their lives. It is a private document that is not intended for communication or information transmission to others. On the other hand, magazines, radio, and television are all media that are designed to disseminate information to a wide audience. Magazines are typically published periodically and contain articles, stories, and other content on various topics. Radio and television broadcast news, entertainment, educational programs, and other forms of content to audiences through audio or visual transmission.

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The SQL statement SELECT Student ID, Surname, House Name FROM Student is used to retrieve information from the "Student" table in a database. It selects and displays the "Student ID," "Surname," and "House Name" fields/columns for all the rows/records in the "Student" table. Therefore, the correct option is "retrieves the listed fields from student table".

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Among the given options, Linux is not a web browser. Firefox, Google Chrome, and Opera are all examples of web browsers. A web browser is a software application that allows you to access and view websites on the internet. It retrieves web pages from servers, displays them on your computer screen, and allows you to interact with them. Firefox, Google Chrome, and Opera are all popular web browsers that are used to browse the internet. Linux, on the other hand, is an operating system that is used to run software applications, including web browsers like Firefox and Google Chrome.

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A file organization that contains a reference number is called "indexed access". In this type of file organization, each record in the file is assigned a unique reference number, also known as an index. The reference number acts as a pointer to the location of the actual data in the file, making it easier and faster to retrieve specific records. Think of it like an index in a book. Just like how you can use the index in a book to quickly find information on a specific topic, you can use the reference numbers in an indexed access file to quickly find the data you need.

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One precautionary measure taken when cleaning a monitor is to unplug the power supply cable. This means disconnecting the cable that provides electricity to the monitor so that it is no longer receiving power. This is important because cleaning a monitor while it is turned on or receiving power can cause damage to the screen or other components, and it can also pose a safety hazard if you accidentally touch the wrong part of the monitor while it is still powered. By unplugging the power supply cable, you ensure that the monitor is safe to clean and that you won't cause any damage to the screen or other components.

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The highest sale by Joy is recorded in cell "E2". This is because the "ITEMS SALES (N)" column represents the sales for each staff member, and "JOY" is located under the "STAFF" column. The sales data for Joy are listed in row 2, and the highest value in that row is found in column "E", which corresponds to the "ITEMS SALES (N)" for Thursday. Therefore, the highest sale by Joy is recorded in cell "E2", which contains the value "400".

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The use of the internet to perform illegal activities is generally called "cybercrime". This includes various types of criminal activities such as hacking, identity theft, online fraud, spreading malware or viruses, online harassment, and more. Cybercriminals use the internet and various online platforms to target individuals, organizations, and even governments to steal personal information, money, or sensitive data. Cybercrime poses a significant threat to cybersecurity and can cause serious financial, reputational, and legal consequences for victims.

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Fourth-generation computer applications cannot execute the operation of "digging of drainages". This is because fourth-generation computers are software-based and designed for specific applications that focus on data manipulation, report generation, and analysis. Fourth-generation applications are known for their ability to process large volumes of data and provide high-level programming languages that make it easy to develop and customize applications for specific business needs. Some common applications of fourth-generation computers include database management, payroll management, financial analysis, inventory control, and other similar functions. However, digging of drainages is a physical operation that requires heavy machinery and human labor, which cannot be executed by a fourth-generation computer application.

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The most suitable type of network for connecting all the computers in the 20 rooms of Mr Francis' office complex into a single network is a Local Area Network (LAN). A LAN is a network that connects computers and devices in a relatively small geographical area, such as a building, a floor, or a group of nearby buildings. Since Mr Francis' office complex has 20 rooms, a LAN would be suitable for connecting all the computers in these rooms into a single network. LANs are designed to provide high-speed connectivity within a limited area, making them ideal for office complexes, schools, and small businesses. They allow for easy sharing of resources such as files, printers, and internet access, as well as efficient communication between users on the same network. In addition, LANs are relatively easy to set up and maintain, making them a cost-effective option for small-scale networking needs. In summary, a LAN would be the best option for Mr Francis to connect all the computers in his office complex into a single network, providing high-speed connectivity, easy resource sharing, and efficient communication between users.

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This question tests disk and data-management terms and the uses of the ATM.

(a) Definitions.

• (i) Disk formatting: the process of preparing a storage disk for use by organising it into tracks and sectors and setting up a file system, which erases any existing data on it.
• (ii) Data backup: making and keeping an extra copy of data on another storage medium so that it can be recovered if the original is lost, corrupted or damaged.
• (iii) Virus scan: the process by which antivirus software examines files, storage devices or memory to detect, and then remove or quarantine, computer viruses and other malware.

(b) Four uses of the Automated Teller Machine (ATM).

• Withdrawing cash from an account.
• Checking the account balance.
• Transferring money between accounts.
• Paying bills and buying airtime (also requesting a mini statement or changing the PIN).

Examination reminder: keep the definitions distinct - formatting prepares/erases a disk, backup duplicates data for safety, and a virus scan detects and removes malware.

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(a) Two safety precautions that can be put in place to protect workstations from foods and drinks are:

Precaution I: The business center can implement a strict no food or drink policy in the vicinity of the workstations. This can be communicated to customers through visible signs and reminders.

Precaution II: The business center can provide designated areas away from the workstations for customers to consume their food and drinks. This will help prevent spillage and other accidents that may damage the workstations.

(b) Two ways the computers can be maintained to ensure efficiency in serving customers are:

Maintenance I: Regular cleaning of computer hardware, such as keyboards and mice, to prevent the buildup of dust and debris that can affect performance.

Maintenance II: Ensuring that computer software is up to date with the latest updates and patches to fix any security vulnerabilities and improve performance.

(c)(i) Three possible health risks to customers while using computers in the center are:

• Risk I: Eye strain and fatigue from staring at the computer screen for extended periods of time.
• Risk II: Repetitive strain injuries (RSI) from frequent typing and mouse usage.
• Risk III: Exposure to germs and bacteria on computer hardware and surfaces.

(ii) Three ways the risks in (c)(i) can be reduced are:

• Solution I: The business center can encourage customers to take regular breaks from computer usage to reduce eye strain and fatigue.
• Solution II: Providing ergonomic keyboards, mice, and chairs that are designed to reduce the risk of RSI can help reduce the incidence of these injuries.
• Solution III: Regular cleaning and disinfecting of computer hardware and surfaces can help reduce the spread of germs and bacteria. The business center can also provide hand sanitizers and encourage customers to wash their hands before and after using the computers.

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(b) Examples of spreadsheet applications:

1. Microsoft Excel
2. Lotus 1-2-3
3. Google Sheets

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This question tests ways of classifying computers, the digital/analog distinction, ICT impact and transmission media.

(a)(i) Three ways of classifying computers.

• By size (supercomputer, mainframe, mini, micro).
• By type/data handled (digital, analog, hybrid).
• By purpose (general-purpose and special-purpose).

(a)(ii) Digital versus analog computers. A digital computer works with discrete data represented as digits (binary 0s and 1s) and gives exact, countable results (for example a desktop PC). An analog computer works with continuous physical quantities that vary smoothly, such as voltage, temperature or pressure, and measures rather than counts (for example a mercury thermometer or a speedometer). In short, digital counts discrete values while analog measures continuous values.

(b) Three positive impacts of ICT on society.

• Faster and easier communication (email, video calls, social media).
• Improved access to education and information through the Internet.
• Efficiency in business, banking and government services (e-commerce, e-banking).

(c) Two types of information transmission medium. Guided (wired) media such as twisted-pair, coaxial or fibre-optic cable, and unguided (wireless) media such as radio waves, microwaves or infrared.

Examination reminder: the digital/analog difference is discrete vs continuous data; and transmission media split neatly into guided (cable) and unguided (wireless).