Plz help (also add full explanation)

The water has been on the stove y=9.5x+62.1 after how many minutes will the tempature be 138.1 f

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%

Solve the system of equations y= 3/2 - 1, -x+ y =-3