What did the waitress say to the neutron when he tried to pay for his meal? “For you, no charge.”

Explain WHY the punchline makes sense!
WILL DO BRAINLIEST IF CORRECT

Explanation:

I don't care about the Brainliest (although it would be nice). Laughter is the best medicine.

If you comma is not there then is the meaning any different?

I think it is because you are not giving your audience a moment to think what's coming. You have to point your audience in the direction you want them to go.

Sorry I misunderstood. The electron has a minus charge. The proton has a plus charge. The neutron has no charge at all (neither plus nor minus). It's a chemistry joke.

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