The heights of men in the USA are normally distributed with a mean of 68 inches and a standard deviation of 4 inches.

**a) **What is the probability that a randomly selected man is taller than 70 inches?

**b) **A random sample of 5 men is selected. What is the probability that the sample mean is greater than 70 inches?

**c) **A random sample of 25 men is selected. What is the probability that the sample mean is greater than 70 inches?