Pls help it is due today

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?

Given that δabc is similar to δdef, which is a possible trigonometric ratio for ∠d? a) tan d = 24 30 b) tan d = 30 24 c) tan d = 18 24 d) tan d = 24 18

Afigure is rotated 180°. if one of the points on the image is g'(4, -8), what were the coordinates of g? (8,4) (8,-4) (4,8) (4,8)