Likely to be viewed with as much acceptance as Catholic nuns running around in thongs, textbook publisher McGraw-Hill Ryerson plans to sell ads in textbooks used by Canadian college students. So in the middle of college physics when Brad Pitt stares up and asks, “Honey, Want A Heineken,” the professor shouldn’t be all that surprised when all the females in class suddenly start squirming in their seats completely forgetting that E=MC2.