A metal circular ring is being cooled. Find the instantaneous rate at which the circumference changes with respect to the radius (measured in centimeters). The instantaneous rate of change is (Type an...

Extracted text: A metal circular ring is being cooled. Find the instantaneous rate at which the circumference changes with respect to the radius (measured in centimeters). The instantaneous rate of change is (Type an exact answer.) cm cm? / cm. cm? cm / cm?. cm / cm.