Ice at −20∘C is added to 50 g of water at 40∘C . When the temperature of the mixture reaches 0∘C , 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 = 4.2 J/g∘C
Specific heat of Ice = 2.1 J/g∘C
Heat of fusion of water at 0∘C=334 J/g )
a. 50g
b. 100 g
c. 60 g
d. 40 g