A boat is towed toward a dock by a cable attached to a winch that stands 10 ft above the water level (see figure). Let 0 be the angle of elevation of the winch and let L be the length of the cable as the boat is towed toward the dock. Complete parts (a) to (c) below. de When L=50 ft, dL =-0.0041. (Round to four decimal places as needed.) de When L=20 ft, = dL 0.0289 (Round to four decimal places as needed.) de dL 10 When L=11 ft, -=-0.1984. (Round to four decimal places as needed.) de c. Find lim L-10 dl. de lim dL and explain what is happening as the last foot of cable is reeled in (note that the boat is at the dock when L=10). What is the value of the limit? (Simplify your answer.)