Problem: The braking distance D in feet required to stop a car traveling x miles per hour on dry, level pavement can be approximated by D=1/9x^2. Provide justifications and citations for your responses.
Required:
Question 1: Calculate the braking distance for 20 miles per hour and 60 miles per hour. How do your answers compare?
Question 2: If the braking distance is 49 feet, estimate the speed of the car.
Question 3: Use a calculator to solve part (b) numerically. Do your answers agree?