n 2 of 14 > The radius of a circular oil slick expands at a rate of 8 m/min. (a) How fast is the area of the oil slick increasing when the radius is 60 m? (Use symbolic notation and fractions where needed.) dA my /min dt (b) If the radius is O at time ? = 0, how fast is the area increasing after 4 min? (Use symbolic notation and fractions where needed.) dA m /min