They both need to be changed after a while for the same reason
Motorist: I was making a U-turn and changed my mind.
They had a reptile dysfunction.
To stop it from falling out.
To really understand acids and bases, you need a pHd.
You hold the lightbulb and every politician screws you!
About 1 in every 500 or 600 million have a chance at becoming human.
Both should be changed regularly, and both for the same reason.
Reasons unknown
1. No mind. 2. No business.