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What was the direct cause of the u.s. entry into world war ii? a. the bombing of pearl harbor b. the invasion of poland by germany c. the capture of belgium by germany d. the battle of britain

Why is it necessary to obey social norms? write briefly.

Why do you think that historians use the word “revolution” to describe important changes in agriculture? how did the green revolution and other agricultural revolutions change the lives of billions of people? < < read less