Once the war started, which major countries fought on what side?
allies central powers

World War I was fought between two major alliances of countries: the Allied Powers and the Central Powers. The Central Powers began as an alliance between Germany and Austria-Hungary. Later the Ottoman Empire and Bulgaria became part of the Central Powers.

Explanation:

to answer this question you need to explain more

i think the answer is c, rivers.

explanation:

sometimes, borders fall along natural boundaries like rivers or mountain ranges. for example, the boundary between france and spain follows the crest of the pyrenees mountains. for part of its length, the boundary between the united states and mexico follows a river called the rio grande. the borders of four countries divide africa’s lake chad: niger, chad, cameroon, and nigeria.