Answer:
the total surface area is 40 + 12 + 15 = 67 square units
Step-by-step explanation:
Refer to the diagram:
the combined area of the top and bottom is 2(5·4) = 40:
the combined area of the ends is 2(1.5·4) = 12; and
the combined area of the front and back is 2( 5 · 1.5) = 15
and so the total surface area is 40 + 12 + 15 = 67 square units
