Blonde and her job interview

A Blonde airhead goes for a job interview in an office.

The interviewer starts with the basics.
"So, Miss, can you tell us your age, please?"

The blonde counts carefully on her fingers for half a minute before replying "Ehhhh... 22!"

The interviewer tries another straightforward one to break the ice. "And can you tell us your height, please?"

The young lady stands up and produces a measuring tape from her handbag. She then traps one end under her foot and extends the tape to the top of her head. She checks the measurement and announces "Five foot two!"

This isn't looking good so the interviewer goes for the real basics; something the interviewee won't have to count, measure, or lookup.
"Just to confirm for our records, your name please?"

The airhead bobs her head from side to side for about ten seconds, mouthing something silently to herself, before replying "MANDY!"

The interviewer is completely baffled at this stage, so he asks - "What in the world were you doing when I asked you your name?"

"Ohhhh, that!" replies the airhead... " I was just running through that song -
'Happy birthday to you, happy birthday to you, happy birthday dear...' "