1. One hundred (100) parts were tested for 10 hours, and 10 failures occurred during the test. The times when the failures occurred are 1, 3, 6, 2, 3, 6, 8, 9, 2, and 1 hour, respectively. What is the failure rate?
2. Field data have indicated that Unit A has a failure rate of 0.0004 failure per hour. Calculate the reliability of the unit for a 150-hour mission.