6. which of the following does not change the form of existing rock?
a. light
c. chemical processes
b. extreme heat
d. tremendous pressure

A. light

Explanation:

Light exposure cannot change a rocks form. Whereas chemical processes can affect a rock from changes in atmosphere, extreme heat can melt rocks, and tremendous pressure can change sedimentary or igneous rocks into metamorphic rock. Hope this helps!

answer: substrate concentration. enzymes work best when there is a high enough substrate concentration for the reaction they catalyse.

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