For 0≤x≤2π, the region under y=cosx and above the x-axis is the common base of two solids. • Solid P has cross-sections perpendicular to the x-axis that are squares. • Solid Q has cross-sections perpendicular to the x-axis that are rectangles whose height is three times their width. What is VQ−VP, the difference between the volumes of the two solids?
a) π
b) 4π
c) 2π
d) 43π