On the distant planet Cowabunga , the weights of cows have a normal distribution with a mean of 454 pounds and a standard deviation of 74 pounds. The cow transport truck holds 15 cows and can hold a maximum weight of 7215. If 15 cows are randomly selected from the very large herd to go on the truck, what is the probability their total weight will be over the maximum allowed of 7215? (This is the same as asking what is the probability that their mean weight is over 481.)