Answer:
B
Step-by-step explanation:
The surface area of this solid is the sum of all the surfaces.
There are 4 rectangular surfaces all around, each measuring 4 by 5 m.
So area of 4 of these surfaces is: 4 * (4*5)= 4 * 20 = 80
The bottom is a rectangle with dimensions 4 and 4. So area is 4 * 4 = 16
There are 4 triangular faces in the top portion, each with base 4 and height 3. Area of triangle is 1/2 * base * height. Hence,
Area of 4 of these triangles is 4*[(1/2)*4*3] = 4 * 6 = 24
Thus, the surface area = 80 + 16 + 24 = 120 m^2
Answer choice B is right.
