Calculate the entropy change of the universe as a result of the following processes :

(a) A copper block of \(600 \mathrm{~g}\) mass and with \(c_{p}\) of \(150 \mathrm{~J} / \mathrm{kg} \mathrm{K}\) at \(100^{\circ} \mathrm{C}\) is placed in a lake at \(8^{\circ} \mathrm{C}\).

(b) The same block at \(8^{\circ} \mathrm{C}\) is dropped from a height of \(100 \mathrm{~m}\) into the lake.

(c) Two such blocks at \(100^{\circ} \mathrm{C}\) and \(0^{\circ} \mathrm{C}\) are joined together.