Perry County is also a part of the larger Harrisburg-York-Lebanon, PA Combined Statistical Area (CSA), which combines the populations of Perry County as well as Adams, Cumberland, Dauphin, Lebanon and York Counties in Pennsylvania.
In mathematics, a function is a relation between a set of inputs and a set of permissible outputs with the property that each input is related to exactly one output. An example is the function that relates each real number x to its square x2.
In mathematics, the trigonometric functions (also called circular functions, angle functions or goniometric functions[1][2]) are functions of an angle. They relate the angles of a triangle to the lengths of its sides.