What caused clashes between early european settlers and native americans?

What is the main social system that existed in ancient china?

Which statement best describes standard oil in the late 1800s? standard oil controlled only a small number of the nation’s oil refineries. standard oil was a single business that operated in a small region. standard oil controlled only the means and methods of oil production. standard oil owned ninety percent of all oil refineries in the united states.

The information box says that the han added 4,000 miles of wall.refer to the mileage scale.how can this be true?