valeria bought a 9 foot length of ribbon from which she wants to cuut 2/3 foot pieces how many pieces can she cut what will be the length of the leftover pirece of ribbon

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%