8. A company distributes its products by trucks loaded at its only loading station. Both, company's trucks and contractor's trucks are used for this purpose. It was found that on an average, every five minutes, one truck arrived and the average loading time was three minutes. 50% of the trucks belong to the contractor. Find out:

(i) the probability that a truck has to wait;

(ii) the waiting time of a truck that waits; and

(iii) the expected waiting time of contractor's trucks per day, assuming a 24 hours shift.

(CA, November, 1996)