A driver in a moving car applies the brakes. The car slows to a final speed of 2.95 m/s over a distance of 40.0 m and a time interval of 7.70 s. The acceleration while braking is approximately constant. (a) What is the car's original speed before braking? mere are several approaches, but in each case, you will need to apply more than one of the constant acceleration kinematics relations. Note that both the acceleration and initial velocity are unknown, while position, final velocity, and time are given. Can you solve a system of two equations for the unknown initial velocity and acceleration? m/s (b) What is its acceleration during this time? (The car's initial velocity is in the positive direction. Indicate the direction with the sign of your answer.) If you have alreauy solved part (a), you now have initial and final velocity, distance, and time. Can you use one of the constant acceleration relations to solve for acceleration with this information? If you have not yet solved part (a), can you solve a system of two equations for the unknown initial velocity and acceleration? Also, what should be the direction of its acceleration be if the speed is decreasing? m/s