Trench warfare was widely used at the beginning of the war but as it progresses modern military tactics such as infiltration tactics using small groups were used
The correct answer here would be Vladimir Lenin, leader of the Bolshevik Revolution that brought communism to power in Russia and established the Soviet Union. Lenin's "New Economic Policy" serves as an example of central planning to bring everything under the central government's control.
Karl Marx and Friedrich Engels were the philosophical founders of communist ideas back in the 19th century.
Josef Stalin was the totalitarian leader that took over the communist leadership in the USSR after Lenin's death.
"Soviets follow Stalin so eagerly despite his atrocities because under the Stalinist Soviet government, people benefited from some social liberalization. Girls were given an adequate, equal education and women had equal rights in employment, improving lives for women and families."
There is not an exact answer, but I believe it is millions.
