A boat capsized and sank in a lake. Based on an assumption of a mean weight of 149 lb, the boat was rated to carry 60 passengers (so the load limit was 8,940 lb). After the boat sank, the assumed mean weight for similar boats was changed from 149 lb to 171 lb. Complete parts a and b below. a. Assume that a similar boat is loaded with 60 passengers, and assume that the weights of people are normally distributed with a mean of 179.8 lb and a standard deviation of 39.1 lb. Find the probability that the boat is overloaded because the 60 passengers have a mean weight greater than 149 lb. The probability is (Round to four decimal places as needed.)