1. X has a normal distribution with the given mean and standard deviation. Find the indicated probability. (Round your answer to four decimal places.) = 43, = 20, find

P(36 X 47)

2. Find the probability that a normal variable takes on values within 0.6 standard deviations of its mean. (Round your decimal to four decimal places.)

3. Suppose X is a normal random variable with mean = 100 and standard deviation = 10. Find a such that

P(X a) = 0.04.

(Round your answer to one decimal place.) a =