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Questions & Answers on General Knowledge.

Question:
When were the first sails used?
Answer:
By 3000 BC, people knew how to tie a cotton sail. Sails allowed people to use wind power instead of muscle power. Now people used ships for trade. By 1200 BC, the Phoenicians and Greeks built trading ships that had special places to store the cargo. By 500 BC, they had ships with two masts.
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