A recent study of the lifetimes of cell phones found the average is 24.3 months. The standard deviation is 2.6 months. IF a company provides its 33 employees with a cell phone, find the probability that the mean lifetime of these phones will be less than 23.8 months. Assume cell phone life is a normally distributed variable.

A. 0.1245

B. 0.1234

C. 0.8643

D. 0.1357

The average yearly Medicare Hospital Insurance benefit per person was $4064 in a recent year. If the benefits are normally distributed with a standard deviation of $460, find the probability that the mean benefit for a random sample of 20 patients is

- Less than $3800

-Less than $4100