So remember that the Surface Area is the sum of all the areas of the faces. But first, we have to convert 9 ft into yds. For this we'll be using dimensional analysis:
[tex] \frac{9\ ft}{1} *\frac{12\ in}{1\ ft} *\frac{1\ yd}{36\ in} =\frac{108}{36} =3\ yds [/tex]
Now that everything is converted to yds, we can form our equation: [tex] SA=2(0.5*3*4)+(4*7)+(5*7)+(3*7) [/tex]
Firstly, do the multiplication: [tex] SA=12+28+35+21 [/tex]
Next, do the addition, and your answer will be SA = 96 yd^2, or the last option.
