What happens when plate subducts and reaches the mantle

How can one distinguish breccia from conglomerate? a. breccia contains angular clasts and conglomerate contains rounded clasts. b. breccia contains rounded clasts and conglomerate contains angular clasts. c. different minerals cement breccia than cement conglomerate. d. breccia contains sand and conglomerate contains silt.

Which subatomic particle has a negative charge

Arailroad car collides with and sticks to an identical railroad car that is initially at rest. after the collision, the total kinetic energy of the two cars is a) the same as before. b) half as much as before. c) one third as much as before. d) one fourth as much as before. e) twice as much as before.