Let the number of phone calls received by a switchboard during a 5-minute interval be a random

Question:

Let the number of phone calls received by a switchboard during a 5-minute interval be a random variable X with probability function
(a) Determine the probability that X equals 0, 1, 2, 3, 4, 5, and 6.
(b) Graph the probability mass function for these values of x.
(c) Determine the cumulative function for these values of X.
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...