Answer:
C. $1638
Explanation:
You want the cost of wax to cover the given composite shaped floor.
Area
The area of the floor can be decomposed into a trapezoid and a rectangle by extending the left vertical line upward.
The trapezoid on the left will have bases of 28 ft and (24-16) = 8 ft, and a height of 12 ft.
The rectangle on the right will have a width of 16 ft and a height of 32 ft.
The total area is the sum of these areas:
(1/2bh + LW) = 1/2(28 +8)(12) +(16)(32) = 728 . . . . square feet
Cost
The cost is found by multiplying the number of square feet by the cost per square foot:
(728 ft²)($2.25/ft²) = $1638
The cost of wax for the floor is $1,638.