A heating coil of resistance, 20 ohms, connected to a 220 V source is used to boil a certain quantity of water in a container of heat capacity, 100 Jkg for 2 minutes. If the initial temperature of the water is 40°C, calculate the mass of water in the container. (Specific heat capacity of water = 4.2 x 10³Jkg 'K', assuming the boiling point of water = 100°C)​