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there did exist liquid water on Mars a drainage channel was cut deeply by Martians there isn’t any life on Mars water had flew on Mars for hundreds to thousands of years
Right Wrong Not mentioned
is not feasible in centuries may be difficult to fulfill might be fulfilled someday in future will take decades of years
confirmative doubtful suspicious cautious
is not feasible in centuries may be difficult to fulfill might be fulfilled someday in future will take decades of years
Right Wrong Not mentioned
confirmative doubtful suspicious cautious
A.were recognized have recognized recognized have been recognized
there did exist liquid water on Mars a drainage channel was cut deeply by Martians there isn’t any life on Mars water had flew on Mars for hundreds to thousands of years
economically possible technologically feasible out of scientific incentive all of the above
have been are had been were
Some urgent needs. Profit or national pride. Economic benefit and national glory. International competition in spac
the Apollo mission was very successful protection from space radiation is no easy job astronauts will have deformed children of grandchildren radiation is not a threat to well protection space explorers
A. were recognized have recognized recognized have been recognized
a. This leads them to believe that Antarctica at one time was a land of swamps and forests. Heat and moisture must have kept the trees in the forests alive. Who call survive the severe cold in the Antarctica and in parts of the Arctic according to the passage The explorers to these areas. All expedition scientists. Any person with good equipment. Only those who are well-equipment.
the Apollo mission was very successful protection from space radiation is not an easy job astronauts will have deformed children or grandchildren radiation is not a threat to well-protected space explorers