8. The vacuum measured to be \( 700 \mathrm{~mm} \) of \( \mathrm{Hg} \) and \( 720 \mathrm{~mm} \) of \( \mathrm{Hg} \) at inlet and outlet of a surface condenser respectively. The barometer reading is \( 760 \mathrm{~mm} \) of \( \mathrm{Hg} \) and the dryness fraction of steam at inlet is 0.92 . Cooling water entering the condenser is at \( 20^{\circ} \mathrm{C} \). Considering no air in the condenser and the temperature rise in cooling water to be maximum determine. (i) The minimum amount of undercooling. (ii) The amount of cooling water required per \( \mathrm{kg} \) of steam.