What were some of the methods used by businessmen to create monopolies?

By eliminating competition to control prices

although world war i began in 1914, the united states did not join the war until 1917. the additional firepower, resources, and soldiers of the u.s. to tip the balance of the war in favor of the allies. remaining neutral. when war broke out in 1914, the united states had a policy of neutrality.

the roman army grew in size and became dominant in the mediterranean region.