PLEASE HELP ME WITH MY MATH ;-; if you help I will give you 5 stars, a thanks, and a brainliest and THIS IS THE LAST ONE

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?

An electrician cuts a 136 foot long piece of cable. one piece is 16 feet less than 3 times the length of the other piece. find the length of each piece

y=2x−1 5x−4y=1 is (1,1)(1,1) a solution of the system?