I am just looking for help on D and E.

Reliability Problem 3 (10 points) An office manager has received a report from a consultant that includes a section on equipment replacement. The report indicates that scanners have a service life that is normally distributed with a mean of 41 months and a standard deviation of 4 months. On the basis of this information, determine the percentage of scanners that can be expected to fail in the following time periods. a. Before 38 months of service. b. Between 40 and 45 months of service. c. Within +/- 2 months of the average service life. d. If the manufacturer of the scanner offers a service contracts of 3 years on these scanners, what percentage of scanners can be expected to fail from wear-out during the service period? e. If the cost of replacement each scanner is $250, and if 1,000 units of this scanner are sold, what is the expected warranty replacement cost to the manufacturer