City water flowing at 0.5 kg/s will be heated from 20oc to 35oc by hot treated boiler water at 140oc. A 15oc hot water temperature drop is allowed. A number of 4.50 m hairpins of 3 in. by 2 in. (schedule 40) double-pipe heat exchangers with annuli and tubes, each connected in series, will be used. Hot water flows through the inner tube. Calculate the heat transfer coefficient in the tube and in the annulus.