. (Data Management) The amount of time between taking a pain reliever and getting relief is normally distributed with a mean of 25 minutes and a standard deviation of 3 minutes. Find the probability...

. (Data Management) The amount of time between taking a pain reliever and
getting relief is normally distributed with a mean of 25 minutes and a standard
deviation of 3 minutes. Find the probability that the time between taking the
medication and getting relief is as follows:
a. At least 30 minutes.
b. At most 20 minutes.
(Hint: Use area under the normal curve.)