After the semester is over, you discover that the math department has changed textbooks (again) so
the bookstore won't buy back your nearly-new book. You and your friend Herman decide to get creative.
You go to the roof of a twelve-story building and look over the edge to the reflecting pool 160 feet
below. You drop your book over the edge at the same instant that Herman chucks his book straight
down at 48 feet per second. By how many seconds does his book beat yours into the water?