Answer:
145.39
Step-by-step explanation:
(9*4)/2=18
18*8.1=145.39
203.67 cm^2
I assume you were asked to find the total surface area.
2 * 4.0 cm * 9.0 cm/2 + 8.1 cm * 7.2 cm + 8.1 cm * 4.5 cm + 9.0 cm * 8.1 cm =
= 203.67 cm^2
