Please help , I'm really struggling with this :(

When a rectangle is dilated, how do the perimeter and area of the rectangle change?

The first-serve percentage of a tennis player in a match is normally distributed with a standard deviation of 4.3%. if a sample of 15 random matches of the player is taken, the mean first-serve percentage is found to be 26.4%. what is the margin of error of the sample mean? a. 0.086% b. 0.533% c. 1.11% d. 2.22%

Let x = a + bi and y = c + di and z = f + gi. which statements are true?