An ostrich 1.5 m tall is walking toward a street light 4 m above the ground at a speed of 5m/s. How fast is the length of the ostrich's shadow

decreasing? At what speed is the tip of the shadow moving? If a is the angle between the light and the ground measured at the tip of the shadow, as shown in the picture, what is the rate of change of a when the shadow is1.5 m long? Length of shadow decreasing at: Speed of tip of shadow: Rate of change of a: