Slices of pizza for a certain brand of pizza have a mass that is approximately normally distributed with a mean of 68.2 grams and a standard deviation of 2.27 grams. a) For samples of size 12 pizza...

Slices of pizza for a certain brand of pizza have a mass that is approximately normally distributed with a mean of 68.2 grams and a standard deviation of 2.27 grams.

a) For samples of size 12 pizza slices, what is the standard deviation for the sampling distribution of the sample mean?

b) What is the probability of finding a random slice of pizza with a mass of less than 67 grams?

c) What is the probability of finding a 12 random slices of pizza with a mean mass of less than 67 grams?

d) What sample mean (for a sample of size 12) would represent the bottom 15% (the 15th percentile)?  grams