What technology did scientists use in the mid-1900's to map the mid-ocean ridge?

How do you believe the japanese justified their imperialism in korea taiwan and china

4. argument take the perspective of a foreign soldier volunteering to serve in the united states in the fight against the british. write a letter to family back home explaining why you have decided to risk your life in this cause. me

What was a major failing of the united states government under the articles of confederation?