Paul Crittenden
Drop everything you know about significant figures, "if it starts with a 1 use 4, everything else use 3." Make sure you know how to draw a fish and write a haiku. Don't mind his dino shrieks. He likes to spend 45 minutes deriving every equation in full then tell you it wont be on the exam. FOR THE LOVE OF GOD DONT SWITCH IMPERIAL TO METRIC.