A student asked his physics instructor "How can you tell which numbers are prime?" Physics instructor: "Oh that's easy! All odd numbers are prime." Student: "What about 9?" Physics instructor: "Oh that's just experimental error!"
A student asked his physics instructor
"How can you tell which numbers are prime?"
Physics instructor:
"Oh that's easy! All odd numbers are prime."
Student:
"What about 9?"
Physics instructor:
"Oh that's just experimental error!"