A stone is dropped into a lake, creating a circular ripple that travels outward at a speed of 50 cm/s. (a) Express the radius r (in cm ) of this circle as a function of time t (in seconds). r(t) = cm (b) If A is the area of this circle as a function of the radius, find A∘r. (A∘r)(t) = Interpret your answer. This formula gives the extent of the rippled area (in cm2) at any time t. This formula gives the circumference of the rippled area (in cm ) at any time t. This formula gives the radius of the rippled area (in cm) at any time t.
