Shina is in her car, stopped at a red light. Her side view mirror is convex with a focal length of f = -7.0m. Looking in the mirror, she notices a car approaching with constant speed. At one moment she estimates the image of the oncoming driver to be located 6.5m behind the mirror. Three seconds later, she estimates the image of the oncoming driver to be located 6.1 m behind the mirror. Use this information to determine the speed of the oncoming car.

Shina is in her car, stopped at a red light. Her side view mirror is convex with a focal length of f = -7.0m. Looking in the mirror, she notices a car approaching with constant speed. At one moment she estimates the image of the oncoming driver to be located 6.5m behind the mirror. Three seconds later, she estimates the image of the oncoming driver to be located 6.1 m behind the mirror. Use this information to determine the speed of the oncoming car.