Zachary purchased a computer for $1,900 on a payment plan 3 months after he purchased a computer his balance was $1,4954 months after he purchased the computer his balance was 1360 what is an equation that models the balance why after x months.

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?