The upper leg length of 20- to - 29-year-old males is normally distributed with a mean length of 43.7cm and a standard deviation of 4.2 cm.

(a) What is the probability that a randomly selected 20-29 year old male has an upper leg length that is less than 40 cm? Round your answer to four decimal places.

(b) A random sample of 9 males who are 20 to 29 years old is obtained. What is the probability that the mean upper leg length is less than 40 cm? Round your answer to four decimal places.

(c) What is the probability that a random sample of 12 males who are 20-29 years old results in a mean upper leg length that is less than 40 cm. Round your answer to four decimal places.