What are the two networks of tubes in vascular plants called?

In this experiment you were asked to present three possible mechanisms. describe those mechanisms here and include drawings of those mechanisms. how will the bromination of trans-cinnamic acid and trans-stilbene allow you to distinguish between the three possibilities? what would you expect to find in your data in each scenario?

In which situations is the principle of cross-cutting relationship useful in determining relative age?

In the diagram below, the northern hemisphere would be in what season at position a a. fall b. winter c. summer d. spring