Calculus and Beer

I am finding too many ways not to study for my upcoming comprehensive exams. I am working on a mathematical review and have found a reason to bear down and make progress. Two mathematicians have developed a formula that explains the growth of those tiny bubbles that make up the head on a glass of beer. By applying this formula, they can optimize the pouring of a glass of beer (they can apply it to a wide variety of much less important but commercially viable situtions too). NOw that's a reason to study math.