The answer is C and A (I think.)
Gl.
D. three-quarters of earth's water is fresh water.
Answer:
D
Explanation:
If NASA had constructed a Space Shuttle without knowing if it would be safe for its passengers, there could be many casualties. So they would test it beforehand using a model, to make sure that it will be safe and sturdy for when they build it.
Third planet is earth.. which has it's atmosphere and support life.,.
that's very different from all other planets<span />
The fear of being alone: Autophobia.
