Answer:
264 cm^2
Explanation:
The solid is a rectangular prism. Every face is either a square or a rectangle.
The top face and bottom face are both squares with a 6 cm side.
The 4 vertical faces are rectangles 6 cm wide by 8 cm tall.
area = 2(6 cm * 6 cm) + 4(6 cm * 8 cm)
area = 2(36 cm^2) + 4(48 cm^2)
area = 72 cm^2 + 192 cm^2
area = 264 cm^2