If the arrival takes place every 10 minutes with a service time 4 minutes per unit then the mean arrival rate, mean service rate and the probability that one would have to wait will be respectively
(a) 10, 4 and 0.25
(b) 0.1, 0.25 and 0.4
(c) 10, 0.4 and 0.25
(d) 0.1, 0.25 and 0.1