Suppose that percent offer is believed to be normally distributed with a mean of 0 30 and a standard deviation of 0 15 a What is the probability that a randomly selected person will offer at least 0 50 of their endowment I b What is the probability that a randomly selected person will offer less than 0 44 of their endowment c What is the probability that a randomly selected person will offer between 0 20 and 0 40 of their endowment