Multiple Choice
When we analyze whether a world is a possible home to life, the key thing we look for is .
A) the presence of organic molecules such as amino acids
B) the past or present existence of liquid water
C) surface coloration changes that could indicate vegetative growth
D) evidence of atmospheric oxygen
Correct Answer:

Verified
Correct Answer:
Verified
Q39: In the Drake equation (Number of Civilizations
Q40: At about what fraction of the speed
Q41: Which of the following is not a
Q42: Why do some scientists think that Jupiter's
Q43: What evidence suggests that life was common
Q45: Why might the presence of a giant
Q46: What is the Fermi Paradox?<br>A)Reasonable assumptions predict
Q47: Briefly summarize current knowledge about the term
Q48: We have sent several spacecraft on trajectories
Q49: How did oxygen (O₂)get into Earth's atmosphere?<br>A)It