Let’s Play Cinematography 13-15

In the movie “Kingdom of Heaven” (2005), Balian creates a method to defend the city, which allows him to obtain more precision and optimize his war resources. This method is the equivalent of using a Cartesian plane to pinpoint a location/time in X (horizontal) and Y (vertical). In the Cartesian plane, X and Y are known as:

What properties must a number satisfy to be a Sheldon prime?

Mathematical story problems are NOT normally used for:

Which of the following numbers is a prime number?