Question: Researchers at a pharmaceutical company have found that the length of time a pain relief drug is effective is normally distributed with a mean of 3 hours and a standard deviation of 45 minutes. For a patient selected at random, what is the probability that the drug will be effective for:

a. less than 2 hour?

b. from 1 to 4 hours?

c. Complete the following sentence: Based on the data I predict that 95% of the people taking this drug will experience pain relief for at least ___ hours. (Round to the nearest tenth of an hour.)

d. What is the probability that the drug will last for less than 1 hour? What 2 things (statistically speaking) might you reasonably conclude if this does happen?