The ½ ordinates of a waterplane 120m long are as follows:

Section AP: ½ 1 1½ 2 3 4 5 6 7 8 8½ 9 9½ FP

½ ord: 1.2 3.5 5.3 6.8 8.0 8.3 8.5 8.5 8.5 8.4 8.2 7.9 6.2 3.5 0 m

Calculate: (16)

(a) Waterplane area

(b) Distance of centroid from midships.