Pls help this is no a homework.

Assume that there is a 4% 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 three independent hard disk drives, what is the probability that during a year, you can avoid catastrophe with at least one working drive?

Asample of 200 rom computer chips was selected on each of 30 consecutive days, and the number of nonconforming chips on each day was as follows: 8, 19, 27, 17, 38, 18, 4, 27, 9, 22, 30, 17, 14, 23, 15, 14, 12, 20, 13, 18, 14, 20, 9, 27, 30, 13, 10, 19, 12, 26. construct a p chart and examine it for any out-of-control points. (round your answers to four decimal places.)

You draw two cards from a standard deck of 52 cards, but before you draw the second card, you put the first one back and reshuffle the deck. (a) are the outcomes on the two cards independent? why?