Life.
They both stand in the middle of the road and stare at your headlights.
It's three letters in. "H".
None, because they keep on asking why all of the other light bulbs in the house aren't being changed at the same time.
Life
With a look over the shoulder.
On your Marx, get set, go!
Because he was trying to make both ends meet.
Because you don't know who is going to make it to the end.