Question

A slab of stone of area 0.36 m square and thickness 0.1 m is exposed on the lower surface to steam at 100 degree c.a block of ice at 0 degree c rests on the upper surface of he slab .in one hour 4.8 kg of ice is melted .the thermal conductivity of slab is latent heat of fusion of ice = 3.36 into 10 raise to power 5 ???????????????