The area approximation given by this Riemann Sum is an {{CMD_14}}{{CMD_15}}overestimate{{CMD_16}}{{CMD_17}}underestimate{{CMD_18}}{{CMD_19}} because {{CMD_20}} {{CMD_21}}the rectangles contain more area than in the region.{{CMD_22}} {{CMD_23}}there is more area in the region than contained in the rectangles.{{CMD_24}} {{CMD_25}}it is impossible to tell.{{CMD_26}} {{CMD_27}}