Adding just one passenger increases your chances of a crash by 48%. Adding another increases those odds by another 158%. Imagine driving at night with two friends yelling into their phones while another kicks your seat to get you to change songs, and your friend in the passenger seat is telling you to speed up because you're late, your cell rings and...well, you get the idea. Keep passengers to a minimum, and when you have them, tell them to keep it down. It's your car, you make the rules.
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