Which expression illustrates the associative property of addition?

What word comes to mind when you hear “associative?” It comes from “to associate, to be grouped together.” Parentheses show the association and the operations in the parentheses are performed first. Notice that the order of the numbers does not change – only the grouping. The associative property becomes important because it allows the mathematician, you, to add or multiply numbers with ease. When you follow the examples below it will become clear how the associative property is used. The associative property can only be used for addition and multiplication, not for subtraction or division.

Understanding what? lol