How do you beat vehicles level 24

First you click on the firetruck on the right. Make sure it is side ways. Then press the black and white bar that holds the bar. Next press on the firetruck that is in front of the black car that will not move. Keep it driving until it pushes the black car is off the screen. Then press the firetruck that pushed the black car once it is in the green spot where there is a big P. then on the screen it should say "Checking" and then say "Next".