A sliding ladder A 13-ft ladder is leaning against a house when its base starts to slide away (see the figure on page 162).

A sliding ladder A 13-ft ladder is leaning against a house when its base starts to slide away (see the figure on page 162). By the time the base is 12 ft from the house, the base is moving at the rate of 5 ft sec. a. How fast is the top of the ladder sliding down the wall then? b. At what rate is the area of the triangle formed by the ladder, wall, and ground changing then? c. At what rate is the angle between the ladder and the ground changing then?(Joel Hass. University Calculus. Pearson/CourseSmart, 01/22/2007. 161). <vbk:PBK9780321551504#page(161)>