The statement in QBASIC that is used to add data at the end of existing sequential file is?

The statement in QBASIC that is used to add data at the end of an existing sequential file is "APPEND".

When you open a sequential file for writing, by default, it starts writing from the beginning of the file and overwrites any existing data. However, if you want to add data to the end of the file, without deleting or overwriting the existing data, you can use the "APPEND" statement.

The "APPEND" statement opens the file for writing, but instead of overwriting the existing data, it positions the write pointer at the end of the file, allowing you to add new data to the file without affecting the existing data.

Here's an example of how to use the "APPEND" statement in QBASIC:

OPEN "my_file.txt" FOR APPEND AS #1
PRINT #1, "This is some new data added to the end of the file."
CLOSE #1

In this example, the "OPEN" statement opens the file "my_file.txt" for appending. The "PRINT" statement writes the new data to the end of the file, and the "CLOSE" statement closes the file.