Trying to figure this out

Estimate the area under the curve f(x) = 16 - x^2 from x = 0 to x = 3 by using three inscribed (under the curve) rectangles. answer to the nearest integer.

Miss henderson wants to build a fence around a rectangular garden in her backyard in the scale drawing the perimeter of the garden is 14 in of the actual length of a b is 20 ft how many feet of fencing what you need

A50-foot ladder is leaning against a vertical wall. if the base of the ladder is 45 feet from the base of the wall, find the angle the bottling of the ladder makes with the ground.