The mean weight of loads of rock is 46.0 tons with a standard deviation of 8.0 tons. If 25 loads are chosen at random for a weight check, find the probability that the mean weight of those loads is less than 44.24 tons. Assume that the variable is normally distributed.
a. 0.1677
b. 0.1357
c. 0.4129
d. 0.2957