Why was placer mining the most widely used method of mining for gold? placer mining gave miners the best chance of striking it rich. placer mining required cooperation between miners and traders. placer mining was affordable to a large number of prospectors. placer mining was practiced by both chinese and native american miners.

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.

australian plates collided into eurasian plates, and the himalayas formed. the andes mountain range the himalayas and the islands of japan form differently. the andes mountain range formed at the convergent boundary of an oceanic plate and continental plate.