A 13-foot ladder is leaning against a vertical wall. If the bottom of the ladder is being pulled away from the wall at the rate of 4 feet per second, at what rate is the area of the triangle formed by the wall, the ground, and the ladder changing, in square feet per second, at the instant the bottom of the ladder is 5 feet from the wall? a) O-- 119 3 b) OJ 119 12 c) O 119 3 d) O- 119 6 e) O- 119 6 A man standing 11 feet from the base of a lamppost casts a shadow 5 feet long. If the man is 6 feet tall and walks away from the lamppost at a speed of 250 feet per minute, at what rate, in feet per minute, will the length of his shadow be changing? a) O 2500 11 b) O- 1250 11 c) O - 1250 11 625 d) 9 71 2500 e) O 11