Aniline is to be cooled from 200 to 150°f in a double-pipe heat exchanger having a total outside area of 70 ft2. for cooling, a stream of toluene amounting to 8,600 lb/h at a temperature of 100°f is available. the exchanger consists of 1¼-in. schedule 40 pipe in 2-in. schedule 40 pipe. the aniline flow rate is 10,000 lb/h.

(a) if flow is countercurrent, what are the toluene outlet temperature, the lmtd, and the overall heat-transfer coefficient?
(b) what are they if flow is parallel?
(c) how much aniline can be cooled if the over-all heat-transfer coefficient is 70 btu/ft2•h•°f?