An animal trainer is teaching a Rottweiler to open an apartment door with its mouth for a scene in an upcoming movie. He gives the dog a treat every time the dog makes progress towards the door. The trainer is using

Arecession is the total value of all goods produced in a country in a given year total value of all goods and services produced in a country in a given year total amount of money earned in a nation over a specific period of time none of the answers are correct.