A car and a motorcycle are stopped at a traffic light. As the light turns green, both the car and the motorcycle start to accelerate at the same time. The motorcycle accelerates at 5 ms/-2 for 4 seconds, and then continues at a constant speed. The car also accelerates for a period of time and then continues at a constant speed. If the car accelerates at 3ms/-2 from the traffic lights, for how long must it accelerate so that the car catches up the motorcycle 30 seconds after the lights turn on green