Farming, fishing
They sell primary resources
Primary means first or basic. The primary sector deals with natural resources. For example oil extraction or meat production. These industries use natural resources to make a product to sell.
oil
Germany.
I am assuming you mean the surrender of Russia in World War I. In WWI, the Russian Empire was at war with Germany. When the Red Russians took over, the new government surrendered to Germany in order to devote more resources to building their new nation. The primary benefit of the withdrawal of Russia to Germany was the elimination of an entire front, allowing Germany to concentrate more on its Western enemies. As part of the treaty (Treaty of Brest-Litovsk--), however, Germany also gained much territory (with its population, natural resources, etc.)
In the study of history, the phrase "primary resources" refers to documents written at or shortly after the events being discussed. I did a web search on that phrase and found helpful website. See the link below.
Germany's submarine fleet.
land and resources
Land
Oil
Coal
dirty