The total number of people of working age who are willing and prepared to work at a given wage rate is the 

A civil engineer who accepts to teach elementary science in a primary school because he cannot get a paid engineering job is an example of?

which of the following is an implication  of a large population

The system of agriculture which involves the cultivation of crops and rearing of animals for family consumption only is termed?

which of the following is a threat to the existence of middlemen