-21 Degrees

Looks like you were right and this was a low stakes bet.

"Wrong! The correct answer is -40 degrees." You answered back to her. Sofia slams her fist on the table in frustration, and hands you the $50 as promised.

You finally break out in a grin and remind Sofia as you head out the door "Study a little harder, and maybe next time you'll get the victorious release you crave!" Heading back home, you are satisfied with the outcome of the tutoring session and the bonus you got.