Protists are to us because they?

select all that

a) make oil

b) produce oxygen

c) make foods

d) break down dead materials

B) Help produce oxygen

C) Help make foods

D) Help break down dead materials

Explanation:

Producing oxygen, making food, and breaking down dead materials are all vital parts of the health of the Earth, animals, and humans. I hope this helps!

1. desertification

2. captive breeding

3. black rhinoceros

4. renewable resources

explanation:

mark brainliest!

all matter is made up of atoms

in any element all atoms are the same

elements in a compound are always in a constant ratio: apex