What is an economic theory that a country’s strength is measured by the amount of gold it has

Mercantilism is the correct answer.

In the mercantilism economic theory, it is believed that a country has to sell more than it buys. In this system, colonies are explored for the benefit of the Mother Country. According to the mercantilism theory, a country's strength, power and success are measured by the amount of gold it has.  

there is often only a small difference between what is legal and what is ethical when working with competitive intelligence..

answer; validity;