Why do we study us history

Describe the technology advancements that lead to explorers being able to sail great distances. [[ps: doesn't explain where. i am only speculating it's in europe.

How did the life of sharecroppers affect their children? children went to school because the farms were small, with little work, children had to work on the farm, so they rarely went to school children learned skilled professions as they worked around the farm. children left home when they became adults because the land wasn't theirs.

Where did khomeini seize power in 1979?