Darryl has a daily goal of earning $100 in profit. His profit is $0.72 per sandwich, and he sold 150 sandwiches today. Explain how Darryl can use the profit rate to determine how much profit he earned. Did Darryl meet his daily goal? PLEASE HELP FAST PLEASE god bless all!!!

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?