A.
In order to calculate the area of the trapezoid, we need to calculate its height:
Using the Pythagorean Theorem, we have:
[tex]\begin{gathered} 21^2=h^2+6^2 \\ 441=h^2+36 \\ h^2=441-36 \\ h^2=405 \\ h=20.12 \end{gathered}[/tex]Now, calculating the area:
[tex]\begin{gathered} A=\frac{(B+b)h}{2} \\ A=\frac{(36+24)20.12}{2} \\ A=60\cdot10.06 \\ A=603.6 \end{gathered}[/tex]B.
If each square yard is $35, first let's convert the area from ft² to yd² (1 yard = 3 feet, 1 yd² = 9 ft²):
[tex]A=603.6\text{ ft}^2=\frac{603.6}{9}\text{ yd}^2=67.07[/tex]So the total cost is:
[tex]\text{cost}=67.07\cdot35=2347.45[/tex]So the cost is approximately $2347.45.