Plzzz help ya girl out due soon

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?

Which demographic challenge is europe currently experiencing? a. an aging and decreasing population b. a baby boomc. an unequal distribution between males and females d. a large group of teenagers moving through the school system(i chose a but i'm unsure)

In a game with three frames, where will the objects on layer 1 appear? a. next to the play area b. in the middle of the game c. behind everything else d. in front of everything else