5.What happens to the grain size of the minerals in rocks when the heat is increased?
A. it increases
B. it decreases
C. it remains constant
D. it degrades intermittently
6.Which of the following is NOT true about metamorphism?
A. slate and gneiss are examples of foliated rock
B. contact metamorphism creates non-foliated rocks?
C. pressure is the main factor of contact metamorphism
D. magma will bake the surrounding rocks due to different in temperature
7.Which of the following rock samples is less influenced by heat?
A. slate
B. schist
C. gneiss
D. phyllite
8.What are the main factors for contact metamorphism to occur?
A. Air and water
B. pressure and temperature
C. heat and reactive fluid
D. temperature and water
9.What is the main factor that affects regional metamorphism?
A. fluid
B. water
C. heat
D. pressure​