A satellite camera takes a rectangle-shaped picture. The smallest region that can be photographed is a 4-km by 6-km rectangle. As the camera zooms out, the length, l, and the width, w, of the rectangle increase at a rate of 3 km/sec. How long does it take for the area, A, to be at least 4 times its original size? a. 9.7 b. 4.94 c. 1.61 d. 3.28