1. The problem statement, all variables and given/known data A 13,000-kg helicopter accelerates upward at 0.37 m/s^2 while lifting a 2000 pound car. To the nearest Newton, what is the lift force exerted by the air on the rotors? 2. Relevant equations I thought since the problem is dealing with forces, I would use F=ma but that wouldn't be the only equation I would use. I know I am dealing with two masses so I don't know how to arrive at the answer.