1.False: The Continental Army held many campaigns agaist the British army. The leadership of General Washington and other officers was crucial to maintane unity and learn from mistakes. The incorporation of a French expeditionary force and a squadron of French navy were crucial to win the war.
2. True: Benedict Arnold was an American General, highly trusted by General Washington. He then tried to betray his fellow brothers, by planning to surrender a fort he had been entrusted to the British. This plan was discovered and then he fought on the British side.
3. False: The Continental Congress didn't hire them. What it did was to give them licenses, making "legal" piracy. This way, by attacking British ships, privateers could trade their prizes and take war prisioners for exchange.
4. False: The Hessians mercenaries were soldiers who served in the British armies as auxiliaries.
5. True: The governor of Spanish Louisina, Bernardo de Gálvez, led many succesfull batles in Mississippi, West Florida.