For each of the following models, write the balance equations and show that they are satisfied by the solution given in Sec. 17.6 for the steady-state distribution of the number of customers in the system.
(a) The M/M/1 model.
(b) The finite queue variation of the M/M/1 model, with K = 2.
(c) The finite calling population variation of the M/M/1 model, with N = 2.