A copper block of mass 80g is placed on ice cube at 0°C (specific heat 80 cal/g). If initial temperature of copper is 100°C. Find amount of water formed during cooling of ice block. (Latent heat of ice is L = 80 cal/g, specific heat of copper 0.1 cal/g-k) :
(1) 10 g
(2) 20 g
(3) 30 g
(4) 40 g