The problem statement is as follows.
Imagine having a cup of magnificent, fresh, hot coffee. Unfortunatly, as it cools down the magnificence level drops sharply. Thus, to avoid such fate, it is desired to minimize cooling.
Assume that the cup is a cylinder with a circle base and the coffee is a "geometric" fluid: always at rest, with its surface perpendicular to gravity.
There are many ways to minimize cooling. One of them is to reduce the exposed surface area of the coffee, by creating an angle between gravitational force and the main axes of the cup. The question is: Given the volume of coffee and parameters of the cup, what angle between the cup's main axis and gravity provides a minimum of exposed surface?
