For a solid whose base is the region bounded by the graphs of y=0 and y=sinx on 0≤x≤π, the cross-sections perpendicular to the x-axis are rectangles. At each x, the rectangle’s height equals twice the square of its base width. Which of the following definite integrals represents the volume of the solid?
a) ∫0π2(sinx)2dx
b) ∫0π2(sinx)3dx
c) ∫0π2sinxdx
d) ∫0π(sinx)3dx