A $1,200 computer is losing value at a rate of 22% per year; 2 years​

Ineed with angles and the measure of them i have abc a is 65 and b is (3x-10) and c is (2x) find the value of x

Find the missing dimension extra points

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?