THE Number of pumps in use at both a six-pump station and a four-pump station will be determined. Give the possible values for each of the following random variables.
a. T = the total number of pumps in use
b. X = the difference between the numbers in use at stations 1 and 2
c. U = the maximum number of pumps in use at either station
d. Z = the number of stations having exactly two pumps in use