<span>We can use rocks to determine if the animals from to day have changed from the past.
Rocks also help us know if rivers once flowed through an area.
We use them to find out what type of animals live then that are extinct now.</span>
Answer:
The answer to your questions is: C. Sulfides
Explanation:
A. Phosphates these compounds do not have sulphur, they are composed by phosphate and oxygen, So this answer is wrong.
B. Sulfates are formed by sulphur and oxygen, not for a metal, then this is not the right answer.
C. Sulfides are molecules formed by a metal and sulphur, this is the anwser to the question.
D. Silicates are formed by sillicon and oxygen, this option is incorrect.
Tiny organisms known as cyanobacteria, or blue-green algae.
