Base your answers to questions 1 through 3 on the cross section provided below. The cross section represents a portion of Earth’s crust. Letters B, C, and D are rock units. 1. List the names of the rock layers in the order in which they were formed. Oldest Youngest 2. Which intrusion (B or C) came after the five rock layers were formed? 3. What was the next event that took place? 4. Draw the symbol for contact metamorphism on rock unit B, wherever it is in contact with the rock layers. (not on top)  FLASHBACK: Describe how each rock type is formed: Igneous Sedimentary Metamorphic