Ice at –20^oC is added to 50 g of water at 40^oC. When the temperature of the mixture reaches 0^oC, it is found that 20 g of ice is still unmelted. The amount of ice added to the water was close to (Specific heat of water = 4.2J/g/^oC Specific heat of Ice = 2.1J/g/^oC Heat of fusion of water at 0^oC= 334J/g)