Question

What is the surface area?

8 mm
10 mm
5 mm
Explain how you arrived at your answer.

Answer 1

340 mm

Explanation:

The formula of the surface area of a rectangular prism is SA=2(wl+hl+hw) where w = width, h= height, l = length. Plugging in all the values from the figure -- 2·(5·10+8·10+8·5)= 340 mm

Answer 2

400 mm

Explanation:

8 * 10 = 80

80 * 5 = 400

400 mm