Coal is carried from a mine in West Virginia to a power plant in New York in hopper cars on a long train. The automatic hopper car loader is set to put72tons of coal into each car. The actual weights of coal loaded into each car arenormally distributed, with mean=72tons and standard deviation=0.6ton.

(a) What is the probability that one car chosen at random will have less than71.5tons of coal? (Round your answer to four decimal places.)

(b) What is the probability that32cars chosen at random will have a mean load weightxof less than71.5tons of coal? (Round your answer to four decimal places.)