One way in which World War 1 changed warfare was "<span>C. By using tanks, airplanes, and machine guns," since these changes were part of what made World War I the first real "total war". </span>
<span>Stalin feared they might spread ideas that went against the Soviet government.</span>
The answer is B. Because as the population continues to grow there will be less fresh water and more salt water.
<span>"to attract the Confederate States to Join the Union" would be your answer
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