Write an equality and then solve it. Sonya is a waitress. She earns $200 a week plus 15% tip in the cost of each meal she serves. What is the least amount of the total cost of the meals she serves in order for her to earn at least $450 each week. Answer this seriously or you’ll be reported

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?