Find the area of triangle QRS. Round the answer to the nearest tenth. A. 19.4 square units B. 91.2 square units C. 1,040.5 square units D. 1,052.4 square unts

The extended version of the link given shows a triangle with sides of measurements equal to 13, 16, and 15 units. 

Since we are given with the measurements of all sides, we use the Heron's formula.

                         A = sqrt ((s)(s - a)(s - b)(s - c))

where s is the semiperimeter and a, b, and c are the measures of the sides.
    
                        s = (a + b + c) /2
                        s = (13 + 15 + 16) / 2 = 22

Substituting this to the equation for the area,
                      A = sqrt ((22)(22 - 13)(22 - 15)(22 - 16))
                            A = 91.19 square units

Thus, the area is approximately equal to 91.2 square units. The answer is letter B.