Can man alter mars environment to make it more suitable for human habitation? how?

The correct answer to this open question is the following.

According to experts of NASA, the probabilities for humans to live in Mars are high, but before this happens, technology must improve considerably to have the proper conditions for human life to prosper on the Red planet.

There are two critical issues that need to be addressed: air and water. Without fresh air, oxygen, and freshwater, humans cannot exist. We would need some kind of proper atmospheric conditions to survive in Mars because the temperature is another key issue. The weather in Mars is below zero conditions and the air has a lot of carbon dioxide, which must change to oxygen for humans to live.

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answer; francis cecil sumner;