The radius of the base of a cylinder is increasing at a rate of 7 millimeters per hour. The height of the cylinder is fixed at 1.5 millimeters. At a certain instant, the radius is 12 millimeters. What is the rate of change of the volume of the cylinder at that instant (in cubic millimeters per hour)? Choose 1 answer: 1512 252 216 126 The volume of a cylinder with radius r and height his rh 2 of 49