How could some of you guys say, blame the parents!!! the kid is 18yrs old he is a young adult. We all know his friends wanted him to push the car.
I have watch some of the Top gear video where they test top speed on a roadway, they have a sign or marker telling them when to start slowing down, or they will end up like the kid and his friends.
I think he miss judge the braking point and could not stop in time.