Heat transfer (45 pt). a single-pass counterflow shell-and- tube heat exchanger is used to warm up liquid glycerin. the heat exchanger comprises "n" tubes of 0.75" and 0.532" outer and inner diameter respectively, and 5m long. liquid glycerin enters the heat exchanger at 16 degc and exits at 60 degc. the mass flow rate of liquid glycerin processed is 5 kg/s. the process uses saturated steam at 1 atm (100 degc, enthalpy of vaporization 2257 kj/kg) on the shell side, which exits the heater as saturated liquid. the shell-side convective heat transfer coefficient can be assumed to be 5000 w/m2k to simplify calculations it can be assumed that the bulk velocity in each tube is 1.80 m/s, all tubes having the same heat transfer coefficient. it can also be supposed that the conductivity resistance of the tube is negligible determine: a) mass flow rate of steam, assuming all the steam is condensed (10 pt) b) log-mean temperature difference (5 pt) c) overall heat transfer coefficient, u (20 pt) d) area of the heat exchanger. how many tubes are required? (10 pt)