The cross-section of a tunnel perpendicular to its length is a trapezium ABCD as shown in the
following figure; also given that:
AM = BN; AB = 7 m; CD = 5 m. The height of the tunnel is 2.4 m. The tunnel is 40 m long.
Calculate:

(i) The cost of painting the internal surface of the tunnel (excluding the floor) at the rate of Rs. 5
per m2
(sq. meter).
(ii) The cost of paving the floor at the rate of Rs. 18 per m2
.