Explanation:
The lateral surface area is the area of the sides, not including the top and bottom.
Assuming the 3×6 rectangles are the top and bottom, the lateral surface area is:
LA = 2×3 + 2×3 + 2×6 + 2×6
LA = 6 + 6 + 12 + 12
LA = 36
The total surface area is the lateral surface area plus the area of the top and bottom.
SA = 36 + 3×6 + 3×6
SA = 36 + 18 + 18
SA = 72