Multiple Choice
What do we understand about the presence of H2O on Venus?
A) There has probably never been a significant amount of water on Venus.
B) In the past, the atmosphere of Venus held significant amounts of water vapor, but it has always been too hot for liquid water to exist on the surface.
C) Oceans of liquid water once existed on the surface, but these evaporated and the water vapor was dissociated by ultraviolet radiation from the Sun.
D) Oceans of liquid water once existed, but this water is now locked up in various rocks on the surface.
Correct Answer:

Verified
Correct Answer:
Verified
Q14: The atmosphere of Venus immediately above the
Q15: The relative rotation patterns of the Venusian
Q16: The dark, seasonal markings on Mars that
Q17: If one were on the planet Venus
Q18: Suppose you observe Mercury at each of
Q20: If you are on Mercury and the
Q21: We have seen that our best Earth-bound
Q22: Carbonate rocks result from:<br>A)compression of frozen CO<sub>2</sub>
Q23: The initial and very rapid recession of
Q24: One nineteenth-century observation, which convinced many of