The time(t) taken to buy fuel at a filling station varies directly as the number of vehicles(V) in a queue and varies inversely as the number of pumps (P), available at the station. In a station with 5 pumps, it took 10 minutes to fuel 20 vehicles. find the;

(a) relationship between t, P, and V;

(b) time it takes to fuel 50 vehicles at a station with 2 pumps;

(c) number of pumps required to fuel 40 vehicles in 20 minutes.