1. The problem statement, all variables and given/known data A man 6 feet tall walks at a rate of 5 feet per second toward a streetlight that is 30 ft high. The man's 3 ft tall child follows at the same speed, but 10 feet behind the man. At times, the shadow behind the child is caused by the man, and at other times, by the child. a) Suppose the man is 90 feet from the streetlight. Show that the man's shadow extends beyond the child's shadow. I solved this by drawing it out and using similar triangles and fairly simple algebra. Man's shadow is 112.5 ft from light. Kid's is 111+(1/9) ft from light. b) The same as a, but with different answers. I solved this the same way. Man's shadow is 75 ft from light. Kid's is 77+(7/9) ft from light. c) Determine the distance from the man to the streetlight at which the tips of the two shadows are the same distance from the streetlight. Same thing. d=80 ft d) Determine how fast the tip of the shadow is moving as a function of x, the distance between the man and the street light. Discuss the continuity of this shadow speed function. This is the part I don't know how to do. I have the answer, since it's in the back of the book, but that doesn't help me. I need to know how to do it. 2. Relevant equations Rules of differentiation. 3. The attempt at a solution I don't know where to start.