Answer: B (130) Explanation: A trapezoidal Riemann sum can be found by multiplying the width (the change in x) of each sub interval by the average of the y values of the two points at either end of the section and then adding up all of the sun intervals. Therefore, the trapezoidal approximation would equal 0.5(40) + 1.5(50) + 1(35) to get the answer of 130.
