name a few scientists/explorer/ social reformer/ inventor/ discovers, who spend most of their lies to find solutions to some major problems,that mankind faced

Dear Student,
There are many scientists, explorers, social reformers, inventors, etc. who spend most of their life finding solutions to some major problems that mankind faced. For example, Thomas Edison invented the bulb to solve the problem of working in the dark at night. Raja Ram Mohan Roy fought against the evils of the Indian society to remove the practice of Sati. Nelson Mandela dedicated his life to fight for the rights of the black people.
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