Problem 1: Can man alter Mars environment to make it more suitable for human habitation? How?
Problem 2: What will happen to the organism if one of the factors that make a Planet Habitable will disappear? Will the organism can survive?
Problem 3: How these factors that make a planet habitable do relate to each other?
Problem 4: Why planet Earth is the most habitable planet in the Solar system?
Problem 5: If you give a chance living on other planets. What would it be like?