Matthew is going to invest in an account paying an interest rate of 5-5% compounded monthly. How much would Matthew need to invest, to the nearest ten dollars, for the
value of the account to reach $221,000 in 17 years?

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?