Assume that there is a ​7% 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 independent hard disk​ drives, what is the probability that during a​ year, you can avoid catastrophe with at least one working​ drive?

With two hard disk​ drives, the probability that catastrophe can be avoided is