But rocks are not unchangeable! Just like the water cycle, rocks undergo changes of form in a rock cycle. A metamorphic rock can become an igneous rock, or a sedimentary rock can become a metamorphic one. Unlike the water cycle, you can’t see the process happening on a day-to-day basis. Rocks change very slowly under normal conditions, but sometimes catastrophic events like a volcanic eruption or a flood can speed up the process. So what are the three types of rocks, and how do they change into each other? Keep reading to find out!
Answer:
Im pretty sure its number 2
Explanation:
Alkali Metals ......................................
A. 22 Million...........................................................
It would be spectral class M
hope this helps
