The lab finds a way to eliminate the oldest cells (more than 3 days old) from its

Question:

The lab finds a way to eliminate the oldest cells (more than 3 days old) from its stock.
Consider again the cells in Section 6.4, Exercises 31 and 32, but suppose that older cells, instead of not staining as often, do not stain as well. New cells have a brightness of 9.5, 1-day-old cells have a brightness of 9.0, 2-day-old cells have a brightness of 8.0, and 3-day-old cells have a brightness of 5.0. Write a random variable describing the brightness, and find its probability and its expectation.
Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most...