The time t taken to buy fuel at a petrol station varies directly as the number of vehicles v on queue and jointly varies inversely as the number of pumps p available in the station. In a station station with 5 pumps, it took 10 minutes to fuel 20 vehicles. Find: i) the relationship between t, p and v; ii)the time it will take to fuel 50 vehicles in the station with 2 pumps; iii) The number of pumps required to fuel 40 vehicles in 20 minutes.​