35-36 Time Rates: Lengthening of shadow and movement of its tip in 3D space

Problem 35
An arc light hangs at the height of 30 ft above the center of a street 60 ft wide. A man 6 ft tall walks along the sidewalk at the rate of 4 ft/sec. How fast is his shadow lengthening when he is 40 ft up the street?

Solution 35

 

Problem 36
In Problem 35, how fast is the tip of the shadow moving?

Solution 36