Based on the clue '18th century frontiersman daniel boone is often de...', what is the answer?

Based on the clue '18th c naturalist georg steller described the sea ...', what is the answer? Based on the clue '18th c poem that says forever cursed be this detes...', what is the answer? Based on the clue '18th century english writer samuel a motel chain ...', what is the answer? Based on the clue '18th century frenchman whose catalogue of fuzzy ob...', what is the answer? Based on the clue '18th century kings ran up debts of hundreds of mil...', what is the answer? Based on the clue '18th century playwright who penned the poem when l...', what is the answer? Based on the clue '18th century schoolkids may have learned the alpha...', what is the answer? What is referred to by '18th century thinker rousseau'?