answer the following questions

Statistics Quiz 6c Name 1. The cruising altitudes for the eet of one commercial airliner are normally distributed with a mean of 34,950 feet and a standard deviation of 1830 feet. What cruising altitude represents the 80th percentile? 2. Pop-It popcorn maker has a mean time before failure of 36 months with a standard deviation of 5 months and the failures are normally distributed. What should be the warranty period, in months so that the manufacturer will have less than 10% of the poppers returned 3. The average time spent sleeping (in hours) for a group of medical residents at a hospital is 6.1 hours with a standard deviation of 1.0 hour. What is the shortest time spent sleeping that would still place a resident in the top 25% of sleeping time