blood donation

A man leaving his apartment building runs into his female neighbor on the elevator.

"Good morning, what are you up to today?" he asks.

She replies, "I'm going down to give blood."

"How much do you get paid for giving blood?" he asks.

"About $40 a pint," she says.

"Hmm ...," the man, says. "I'm going up to donate sperm, and the sperm bank pays $100 a tablespoon."

The woman is left with a questioning expression on her face as the man leaves the elevator.

The next day they meet in the elevator again.

The man asks, "So, where are you off to, today?"

"Fmerm mank," she says, with her mouth full.