Pls help I’m failing ASAP

Why is it useful for historians to base certain studies on the analysis of historical periods

What is the significance of the battle of saratoga? a. the defeat at saratoga allowed the british to invade new england by land. b. after the defeat at saratoga france refuse to sign a treaty with the united states. c. the british won a decisive victory at saratoga. d. after the victory at saratoga france gave open support to the united states including arms money and ships.

Select all that apply. identify two reasons for the fall of the ming dynasty. invasion by the japanese and koreans death of the emperor invasions poor leadership