Answer:

The SCREEN statement must be before any graphics statement. If you run the program:

'Put a spot on the screen at column 30 row 50
PSET (30, 50)
SCREEN 12
END

you will get an error message:

Illegal Function Call

This means that since you did not start graphics first, the QBasic system can't do the PSET statement.

`PSET`

Here is the correct version of the program:

'Put a spot on the screen at column 30, row 50
SCREEN 12
PSET (30, 50)
END

The SCREEN statement starts up the graphics hardware so that now other graphics statements can be done.

The PSET statement stands for Pixel Set. A pixel is a dot on a computer graphics screen. Pixel stands for picture element. "Set" means to "turn on," so this statement turns on one dot on the screen. All computer graphics pictures are made of thousands of pixels. The PSET statement looks like this:

PSET (column, row)

Column and row can be numbers or variables. The part of the statement (column, row) says where on the graphics screen to set the pixel.

Answer:

PSET

QUESTION 3:

`PSET`