Helppp pls..s

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?

Which polygon is she in the process of constructing ?

Which of these would have been most likely to have been a carpetbagger during the reconstruction era? a) a new york businessman who relocated to mississippi b) a former slave who was able to buy land in birmingham c) a carolina-born politician who supported the democratic d) a former confederate officer who owned a farm in memphis eliminate