5. The gas tank of a parked pickup truck develops a leak. The amount, V, in litres, of gas remaining in the tank after t hours can by modelled by the function 2 V = 60 2 - , Osts 10 a. How much gas was in the tank when the leak developed? b. How fast is the gas leaking from the tank at t = 7 h? C. How fast was the gas leaking from the tank when there is 15 L of gas in the tank