Some thinking and some laughing

To make up for all of my whining about my TA situation (which still currently sucks), here is a little "riddle" from my sister-in-law. For the answer, click on the "Comments" at the bottom of this post!

You are driving in a car at a constant speed. On your left side is a 'drop off' (the ground is 18-20 inches below the level you are traveling on) and on your right side is a fire engine traveling at the same speed as you. In front of you is a galloping horse, which is the same size as your car and you cannot overtake it. Behind you is a galloping zebra. Both the horse and zebra are also traveling at the same speed as you. What must you do to safely get out of this highly dangerous situation?