Suppose babies born in a large hospital have a mean weight of 4088 grams, and a variance of 55,696. Of 128 babies are sampled at random from the hospital, what is the probability that the mean weight of the sample babies would be greater than 4132 grams

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?