Abranch of mathematics that uses variables is called?

Fine the area of the kite. a. 90 sq. units b. 9 sq. units c. 180 sq. units d. 45 sq. units

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%

Which exponential function has an initial value of 2? f(x) = 2(3x) f(x) = 3(2x)