differential calculus rate of change problems

1.) Johann is 6 ft. tall and he walks at a rate of 5 ft/sec toward a street light that is 16 ft above the ground. At what rate is the tip of his shadow moving? At what rate is the length of his shadow changing when he is 10 ft from the base of the light?

2.) A light is at the top of a pole 50 ft high. A ball is dropped from the same height from a point 30 ft away from the light. How fast is the shadow of the ball moving along the ground 0.5 second later? (assume the ball falls a distance s = 16t^2 ft in t seconds).