What factors contributed to the westward expansion of the u. s.?

multiple answers


increased immigration
the cold war
the discovery of gold
the homestead act
the quest for land, wealth, and adventure
the revolutionary war

radiative zone

explanation    

radiative zone is the layer of the sun which energy is transferred away from the core by radiation. although, the core is the only part of the sun that produces an appreciable amount of heat through fusion. in fact, 99% of the energy produced by the sun takes place within 24% of the sun's radius.