1. What evidence do we have that the surface features on Mercury were not formed during recent geologic history? 2. Venus takes 440 days to move from greatest western elongation to greatest eastern...

1. What evidence do we have that the surface features on Mercury were not formed during recent geologic history?

2. Venus takes 440 days to move from greatest western elongation to greatest eastern elongation, but it needs only 144 days to go from greatest eastern elongation to greatest western elongation. With the aid of a diagram, explain why.