Every program that interacts with people responds to a specific set of commands. The set of commands and the syntax for entering them is called the user interface and varies from one program to another. The DOS operating system makes a distinction between internal and external commands.
You right click the mouse. hope this helps
Answer:
B and C
Explanation:
xPos and yPos determine the center of the circle, and rad determines the radius of the circle drawn.
It cannot be A because it starts drawing a circle with the center of (4, 1). None of the circles ahve a center at (4, 1). It is B because while it does start at (4, 1), the repeat function adds one to the y and radius. While ti repeats 3 times it ends up drawing all 3 circles. C also works because it starts by drawing the biggest circle and then subtracting the values to make the other two. It cannot be D because in the repeat function it subtracts from the y value and radius too early, it doesn't draw the biggest circle.