Answer:
540 ft^2.
Step-by-step explanation:
The area of the trapezoid = h/2 (10 + 18) = 14h.
By Pythagoras the height h = √(5^2 - 4^2) = 3.
So the area of the 2 trapezoidal bases = 2 * 14*3
= 84 ft^2.
Now we calculate the area of the four lateral rectangular sides:
= 10*12 + 18*12 + 2*5*12
= 456 ft^2.
Total area = 456 + 54
= 540 ft^2.
