1. Assume that the erythrocyte count of the normal male adult in a certain area is normally distributed, with a mean of 5.4×1012 / L and standard deviation of 0.43×1012 /L. Answer the following questions:

(a) What is the probability of erythrocyte counts of less than 4.1×1012 / L ?

(b) What is the probability of erythrocyte counts of more than 6.7×1012 /L ?

(c) What is the probability of erythrocyte counts in [4.1, 4.8]×1012 /L?