Help pLEASE! be sure its right!!

Choose a second initial value that is 0.01 greater than the initial value from question 9. iterate it using the function, f, ten times. if necessary, you can round your results to the nearest ten-thousandth.

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%

Anyone? 15m is what percent of 60m; 3m; 30m; 1.5 km?