Researchers at a drug company are testing the duration of a new pain reliever. The drug is normally distributed with a mean duration of 240 minutes (4 hours) and a standard deviation of 40 minutes. The drug is administered to a random sample of 10 people. (Round means, standard deviations, and z-scores to the nearest hundredth, if necessary.) 1. What is the population mean? 240 in minutes) 2. What is the population standard deviation? 40 (in minutes) 3. What is the sample size? 10 4. Can normal approximation be use for this problem? Yes, the sample size is large enough to assume that the sample distribution is approximately normal. + 5. What is the mean of the sample means? 240 (in minutes) 6. What is the standard deviation of the sample means? 12.65 What is the probability that the drug will wear off in less than 200 minutes? 1. What is the z-score? 2. What is the requested probability? P(I What is the probability that the drug will wear off after 220 minutes? 1. What is the z-score? 2. What is the requested probability? P(x What is the probability that the drug will wear off between 200 and 220 minutes? 1. P(200