Answer Happy

Question 9 (9 marks) A water tank containing 500 litres of water begins to leak. The volume (1) of water remaining in the tank at timer minutes after the leak begins is given by Vestres, where , is the original volume of water in the tank. (a) Show that kV. dV dt (b) (i) if the water is leaking out at a rate of 3 litres per minute at the instant when the volume is 300 litres, show that = -0.01. N 12 [2] [2] (ii) Hence, find exactly, the time taken for the volume of water remaining in the tank to fall to half of its original volume. [5]