Question

PLEASE ANSWER THIS! I WILL GIVE AMAZING RATING IF FAST

Answer 1

`\boxed{\sf a) \ 120 \ km^2}`

Explanation:

The surface area is the total area of the faces added together.

Area of 2 triangles + Area of 3 rectangles

The two cross-sections are the triangles.

Area of triangle = base × height × 1/2

Area of a rectangle = length × width.

4 × 3 × 1/2 + 4 × 3 × 1/2 + 9 × 3 + 9 × 4 + 9 × 5

6 + 6 + 27 + 36 + 45

= 120