Until the very latest moment of his existence, man has been bound to the planet on which be originated and devel- oped. Now he had the capability to leave that planet and move 71. __________ out into the universe to those worlds which he had known previously only directly. Men have explored parts of the moon. 72. __________ put spaceships in orbit around another planet and possibly within the decade will land into another planet and explore it. Can we be 73. __________ too bold as to suggest that we may be able to colonize other 74. __________ planet within the not-too-distant future? Some have advocated 75. __________ such a procedure as a solution to the population problem: ship the excess people off to the moon. But we must keep in head the 76. __________ billions of dollars we might spend in carrying out the project. To maintain the earth's population at its present level, we would have to blast off into space 7,500 people every hour of every day of the year. Why are we spending so little money on space ex- 77. __________ ploration? Consider the great need for improving many aspects 78. __________ of the global environment, one is surely his concern for the money and resources that they are poured into 79. __________ the space exploration efforts. But perhaps we should look at both sides of the coin before arriving hasty conclusions. 80. __________
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