A pair of shoes sells for $400 and 35,000 are sold a month. The company did some research and realized that for each $25 decrease in price, they can sell 4375 more
pairs of shoes per month.
How much should the company charge for the shoes so they can maximize monthly
revenues?

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?