What is the federal system known as ?
Republic
Democracy
Monarchy
Autocracy

I’d say either a republic or democracy

Explanation: hope this helps a bit

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 believe your answer is mountains.