To find the surface area of both triangular bases of the net, we need to use the formula for the area of a triangle, which is:
\[ \text{Area} = \frac{1}{2} \times \text{base} \times \text{height} \]
From the description, each triangular base has a base of 5.5 feet (as indicated by the dimensions of the rectangles to which the triangles are attached) and a height of 3.5 feet (one of the legs of the triangle).
So the area \( A \) of one triangle can be calculated as follows:
\[ A = \frac{1}{2} \times 5.5 \times 3.5 \]
Since there are two identical triangular bases, the total surface area \( SA \) of both triangular bases would be:
\[ SA = 2 \times \left(\frac{1}{2} \times 5.5 \times 3.5\right) = \frac{1}{2} \times 2 \times 5.5 \times 3.5 = 5.5 \times 3.5 \]
Finally, we can express this as:
\[ SA = 2 \left(\frac{1}{2} (5.5)(3.5)\right) \]
However, the correct choice from your responses would be based on the dimensions provided for the triangle, which matches the equation:
\[ SA = 2\left(\frac{1}{2}(3.5)(5.5)\right) \]
So the correct answer is:
\[ SA=2\left(\frac{1}{2}(3.5)(5.5)\right) \]