Step-by-step explanation:
what's the problem ?
you need to calculate the area of each rectangle and sum them all up.
that is then the total surface area of the whole prism (or "box").
we have 2 rectangles of 4×3.8
2 rectangles of 11.5×3.8
and 2 rectangles of 11.5×4
so, the total is
2×4×3.8 + 2×11.5×3.8 + 2×11.5×4 = 30.4 + 87.4 + 92 =
= 209.8 m²
