Which model of the universe gives the youngest age for its present size and expansion rate?
A) a critical universe
B) an accelerating universe
C) a re-collapsing universe
D) a coasting universe
E) All models give the same age.
Question 2
Which of the following does not provide evidence that Mars once had abundant liquid water on its surface?
A) the presence of features that look like dried up river beds
B) the presence of what looks like sedimentary layers in some crater bottoms
C) the presence of very old craters that appear to have been eroded by rain
D) the presence of canali, discovered in the late 1800s by Giovanni Schiaparelli and mapped by Percival Lowell