The document defines key economic concepts: 1) Economics studies how people make choices to satisfy unlimited wants with scarce resources. Scarcity occurs when resources cannot meet all needs and desires. 2) The three factors of production are land, labor, and capital. Land includes natural resources, labor is human effort, and capital consists of tools and machines. 3) A production possibilities frontier on a graph shows the maximum possible output combinations of two goods an economy can produce with limited resources.