題目
11. Let be the region bounded above by the graph of and below by the graph of .
(A) falls into the region .
(B) The area of can be represented by .
(C) The area of is equal to 4.
(D) The region is the base of a solid. For this solid, each cross section perpendicular to the -axis is a square. The volume of this solid is equal to .
(E) The region models the surface of a small pond. At all points in at a distance from the -axis, the depth of the water is given by . The volume of water in the pond is equal to .