Studies show that sunscreen is too expensive, and it probably encourages people not to use enough. Also, unequal pay for women is still very much a thing in medicine. John Green -- Executive Producer Stan Muller -- Director, Producer Aaron Carroll -- Writer Mark Olsen -- Graphics http://www.twitter.com/aaronecarroll http://www.twitter.com/crashcoursestan http://www.twitter.com/johngreen http://www.twitter.com/olsenvideo And the housekeeping: