Answer:
C. 40.5 cm²
Explanation:
Use the formula for the area of a trapezoid:
A = (1/2)(b1 +b2)h
The bases are the parallel sides, 4.5 cm and 9 cm. The height is the perpendicular distance between them, 6 cm. Filling in these numbers, we have ...
A = (1/2)(4.5 +9)(6) = 40.5 . . . cm²