Stone Age people used caves as:

Shelter

Homes

schools

is this an essay or multiple choice

by using  production possibilities graph.  opportunity costs are key expenses in financial matters and are utilized as a part of registering money saving advantage investigation of a venture. such expenses, be that as it may, are not recorded in the record books but rather are perceived in basic leadership by processing the money costs and their subsequent benefit or misfortune.

i’m   sure probably just geuss and see which one you can get right, i’m pretty sure it is the combination of goods and services

answer; proximity;