Given a normal population whose mean is 515 and whose standa

Given a normal population whose mean is 515 and whose standard deviation is 25, find each of the following:

A. The probability that a random sample of 3 has a mean between 518 and 522.

Probability = ?

B. The probability that a random sample of 19 has a mean between 518 and 522.

Probability = ?

C. The probability that a random sample of 24 has a mean between 518 and 522.

Probability = ?

Please help me understand what to do and how to do it. Thank you.

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