This NBA season hinges on the kind of bonds the contenders concoct in the lab -- or at least on the court. But if chemistry were the only subject that mattered, the Spurs would be working on one for the thumb -- the second thumb. So we're taking a look at how each of the 30 NBA clubs fares in a variety of subjects: Chemistry, yes, but also Biology, because trainers countrywide will be working overtime to ready hobbled or aging stars; Economics, because salary caps and team finances are as formidable an opponent as Dwight Howard in the paint; History, because what has happened before has happened for a reason; and Math, because, the numbers -- well, ESPN Insider John Hollinger's anyway -- never lie. (And don't forget about Geography.) Our report cards are tough but fair. And before you tell us that the overall mark doesn't add up -- c'mon, haven't you heard of grading on a curve?