Answer:
The correct option is A.
Step-by-step explanation:
The area of a triangle is
[tex]A=\frac{1}{2}\times base\times height[/tex]
From the given figure it is clear that the base of the triangle STR is 6 ft and the height of the triangle 10 ft. So, the area of triangle STR is
[tex]A=\frac{1}{2}\times 6\times 10[/tex]
[tex]A=3\times 10[/tex]
[tex]A=30[/tex]
The area of triangle STR is 30 square ft. Therefore the correct option is A.
