Equilibrium in a competitive market results in the greatest amount of economic surplus from the production of a good or service

The slope of the AE curve is .80. What is the expenditure multiplier? Everything else the same, by how much does equilibrium aggregate expenditure increase if

a. exports increase from $1.75 trillion to $2.25 trillion? b. government expenditure on goods and services decrease from $2.0 trillion to $1.8 trillion? c. investment increases from $1.2 trillion to $2.3 trillion?

The mercantilist economic doctrine was widely followed from the sixteenth to the eighteenth century in Europe

Mercantilists advocated the use of tariffs to restrict trade as they believed that countries that export more than they import will increase wealth. What could be the problem with such an economic policy?