Everyday, Kevin has to drive 7 miles each way to work and back. At work, he has to drive his truck on a 296-mile delivery route. How many miles does he drive during a 5-day workweek?

Assume that there is a 11% rate of disk drive failure in a year. a. if all your computer data is stored on a hard disk drive with a copy stored on a second hard disk drive, what is the probability that during a year, you can avoid catastrophe with at least one working drive? b. if copies of all your computer data are stored on four independent hard disk drives, what is the probability that during a year, you can avoid catastrophe with at least one working drive?