The average time it takes a group of adults to complete certain achievement test is 46.2 minutes. The standard deviation is 8 minutes. Assume the variable is normally distributed.

A.) Find the probability that a randomly selected adult will complete the test in less than 43 minutes.

B.) Find the probability that, if 50 randomly selected adult take the test, the mean time it takes the group to complete the test will be less than 43 minutes.