How did scientists figure out how old the rocks in the Mid-Atlantic Ridge are? A. Radiometric dating
B. Taking photographs
C. Watching it grow
D. Asking other people

A because that’s the only way they could really figure it out

It is the doctrine that the us had the right and duty to expand throughout north america. it just means they believed they had the right to expand westward and they did! they stated with the 13 colonies and then they kept moving gaining different territories throughout the years

Answerwide-open;