Economy no: 6

 Economy:

(example):

let's say that you on average, get 3 rabbits, and 200, berries.

if you want to catch more rabbits, then you must give up berries,

and if you want 4 rabbits you need to give up 150 berries.

That the Opportunity cost catching more rabbits

Economy no: 5

 Economy:

Scarcity is the main reason You need economics.

Because people want infinite food but it is finite to we have to allocate to people.