Water (7.5 kg/s) is to be heated from 85°c to 99°c in a shell-and-tube heat exchanger. condensing steam at 400 kpa supplies the necessary energy. the exchanger consists of 1-shell-pass (2- tube-passes of thirty 2.5-cm outside-diameter tubes per pass). the overall heat transfer coefficient is 2500 w/m²-k. a. what is the corrected log mean temperature difference? b. what is the heat transfer rate in w? c. what is the tube length?