A heavy machine rejects a liquid at `60^(@)C` which is to be cooled to `30^(@)C` before it is fed back to the machine. The liquid rejected by the machine is kept flowing through a long tube while it is cooled by 60 liter water surrounding the tube. The initial temperature of the cooling water is `10^(@)C` and it is `20^(@)C` when it is changed after 1 hour. Calculate the amount of liquid that passes through the tube in one hour. Specific heat capacity of the liquid and water are `0.5 calg^(-1) .^(@)C^(-1)` and `1.0 calg^(-1).^(@)C^(-1)` respectively.
