It may be easier to demonstrate surface tension to said 7th grader than explain it. Float a needle on water in a bowl. By way of explanation, the water molecules are "clinging onto each other" in the bowl, and the tiny forces with which they hang onto each other create surface tension. The vast numbers of water molecules hanging onto each other in the water that's in the bowl are acting like a very, very thin piece of fabric or cloth on the surface of the liquid.

historical method

observational method

expermental method

How is the method superior to the payback method

How is the method superior to the payback method

Declaring a method is when you code for what the method will perform. When you call a method, you are using the method you have written in another part of the program, (or inside the method if it is recursive).