What does it mean to say that something is "enrgy efficient"?

Energy efficiency is how much of the used energy from a product is not unwanted. The fewer unwanted energy the more energy efficient it is.  

Explanation:

the tariff was created to protect industry in the northern part of the united states. industries in the north were being driven out of business by imported goods that were priced at a low rate. the goal was to protect these industries   by taxing the goods.

this means that germany had to pay the allied countries. reparations are/is essentially payment for something that they have done wrong, so after ww1, germany was forced to pay reparations so they could replenish the allied countries resources' that they had lost during the war.