The daily dollar sales of a large retail "Big Box" store, measured in 1,000 dollar units, is a random variable, \(D\), that has an expectation of 20.

(a) Provide an upper bound to the probability that dollar sales exceed 40,000 dollars on a given day.

(b) If the variance of \(\mathrm{D}\) is 4, define an interval in which dollar sales will occur on any given day with probability \(\geq .95\).