Exams At UNC

This sophomore reported for her UNC final
examination which consists of "yes/no" type
questions.

She takes her seat in the examination hall,
stares at the question paper for five minutes,
and then in a fit of inspiration takes her purse
out, removes a coin and starts tossing the
coin and marking the answer sheet - Yes for
Heads and No for Tails. Within a half an hour,
she is all done whereas the rest of the class
is sweating it out. During the last few minutes,
she is seen desperately throwing the coin,
swearing and sweating.

The professor, alarmed, approaches her and
asks what is going on.

"I finished the exam in half an hour. But,"
she says, "I am rechecking my answers."