A cistern 7 m long and 5 m wide contains water up to a breadth of 1 m 40 cm. Find the total area of the wet surface.
Choose the correct choice from the following options:
A) 69 m sqaure  B) 49 m sqaure  C) 52 m sqaure  D) 64 m sqaure  E) None of these
Explanation:   69 m sqaurerea of the wet surface =   2[lb+bh+hl] - lb = 2 [bh+hl] + lb   = 2[(5*1.40+7*1.40)]+7*5 = 69 m square   Option 69 m sqaure
<result>A</result>
A cistern 7 m long and 5 m wide contains water up to a breadth of 1 m 40 cm. Find the total area of the wet surface.