stress

The magnitude of stress proceeding an exam is inversely proportional to the number of days remaining before the day of the exam. At the same time, the student's inclination to procrastinate, is the square root of the magnitude of stress. 

From this data, it is possible to set up an expression for the stress levels of a given student, prior to a major exam. We can then use implicit differentiation to observe the rate at which the student descends into madness, however, if I do this, we may have to multiply "inclination to procrastinate" by a factor of 3.