1. According to a study, it takes an average of 345 minutes for taxpayers to prepare, copy and e le an income tax return. The distribution of times follows a normal distribution and has a standard deviation of '50 minutes. A random sample of 45 taxpayers is picked; a.' What is the zscore if the sample mean is 360 minutes? b. What is the probability of obtaining a sample mean greater than 360 minutes? c. What is the z-score if the sample mean is 337 minutes? d. What is the probability of obtaining a sample mean that is between 337 and 360 minutes? (Hint: Use the same process as you did in chapter 5 when there were two observation points on opposite sides of the mean)