please explain and show work neatly, answers found in the post

2. The petroleum fraction of Example 4.2 flows at a rate of 1200 lb/h in the annulus of a 4-in. multi-tube hairpin exchanger having seven tubes, each with 20 fins. The fin thickness is 0.035 in. and the hairpin length is 15 ft. Other pipe and fin dimensions are given in Table 4.2. Calculate the following: (25 Points) (a) The flow area for the annulus. (4 Points) (b) The equivalent diameter for the annulus. (4 Points) (c) The Reynolds number for the oil. (4 Points) (d) The heat-transfer coefficient for the oil. (4 Points) (e) The friction factor for the oil. (4 points) (1) The friction loss per unit length in the annulus. (5 Points) 11 LE Ans. (a) 0.0521 ft. (b) 0.0276 ft. (c) 1314. (d) 19.1 Btu/h ft?: F. (e) 0.487 (1) 0.00156 psi/ft. A double-pipe heat exchanger consists of two hairpins connected in series. Each hairpin is 20 ft long