5. If a random variable has a normal distribution with mean 80 and standard deviation 20, what is the probability that it assumes the following values?

(a) Less than 77.4

(b) Between 61.4 and 72.9

(c) Greater than 90.0

(d) Less than 67.6 or greater than 88.8

(e) Between 92.1 and 95.4

(f) Between 75.0 and 84.2 (g) Exactly 81.7