could you review this and tell me if i am correct...part B stumped me.

The weights of ice cream cartons produced by a manufacturer are normally distributed with a mean weight of 10 ounces and standard deviation of 0.5 ounces. A) what is the probability that a randomly selected carton has a weight greater than 10.21 ounces? To find the probability that it has a weight greater than 10.21 ounces, I first found the mean and standard deviation values, which is as follows: Mean: 10 ,Standard Deviation: 0.5Then, I took 10.21 and the values listed above, and plugged them into the excel formula. This got me 0.6628 which I then subtracted from one since the question asks for 'greater than'. Therefore, the answer to part A would be 0.3372 B) You randomly select 25 cartons. What is the probability that their mean weight is greater than 10.21 ounces? i wasnt really sure how to get this answer, but i believe to get this answer you have to divide the decimal 0.3372. Therefore i think the answer to part B would be 0.0135

C) Compare the probabilities from parts (a) and (b).

not sure what to do for c