Laam

A man bought a cake and ate 1/7 from it immediately. Two hours later, hea ate 2/5 of the remainder and then gave 1/4 of the cake that is left to his cat. Calculate the fraction of the cake is left.

How much ice initially at -4 °C is needed to cool down 250 g of water at 80 °C to 0°C? Take the specific heat capacity of ice to be 2060 J kg-1°C-1