Answer:

Step-by-step explanation:
see the attached figure to better understand the problem
we know that the area of the room is equal to the area of a rectangle plus the area of a trapezoid
step 1
Find out the area of the rectangle

step 2
Find out the area of the trapezoid

step 3
Sum the areas

substitute the values

Answer:
The answer is C
Step-by-step explanation:
..... 40.5 ...............