The ancient water erosion features on the surface of Mars suggest that the planet must have had a much
A) warmer, thinner atmosphere in the past
B) cooler, thicker atmosphere in the past
C) cooler, thinner atmosphere in the past
D) warmer, thicker atmosphere in the past
Question 2
An amoeba is an example of a
A) multicellular prokaryote
B) multicellular eukaryote
C) unicellular prokaryote
D) unicellular eukaryote