I Know This - A sarcastic phrase used to mock slow people who say or ask s

A sarcastic phrase used to mock slow people who say or ask something really dumb. Usually written as "i knaa" and comes from West Philly.

"I knaa!" he said, after his friend asked what 2 + 2 was.

"I knaa!" she said, after her friend asked what a triangle was.

"I knaa!" he said, after his friend asked what the word 'no' meant.