Sokal and rohlf 1981 studied purebred Canadian dairy cattle. The butterfat percentages from 2-year-old cows follow a normal distribution with a mean of 4.51 and a standard deviation of 0.348.
a. Find the probability that a 2 year old cow will have a butter fat percentage between 4.25 and 4.60
b. Find the probability that a 2 year old cow will have a butterfat percentage less than 4.75