4.) How many tests did Griffith perform?

its temperature is increasing. this causes molecular vibrations to increase.

all these collisions do one thing, and that thing is explained in the last option. when dusst, rocks and ice collide, they harden and form giant layers of rocks or hard ice.

d)   to harden materials to form different parts of earth’s layers

hope it ,

bioteacher101

answer///africa and asia;