Amy has a crush on Jake. Amy is hot on Jake's heels, and they are both cycling at the same constant velocity some distance apart. Jake engages the brakes and coasts to a stop at constant deceleration over a distance d = 20 m. At the exact moment Jake comes to a stop, Amy engages her brakes and coasts to a stop at the same constant deceleration. Coincidentally, Amy stops exactly where Jake is. How far behind Jake was Amy at the start?