Write a sine or cosine function for the data set

Jan: 39
Feb: 42
Mar: 50
Apr: 72
Jun: 80
Jul: 86
Aug: 77
Oct: 66
Nov: 55
Dec: 44

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%

Write a fraction less than 1, which has a denominator of 6 and is greater than 3/4 plz answer !

Solve for x where 0 equation: cot^2x+2cotx+1=0