Answer: Vitamins
Explanation:
they are nutrients that are made by living things
Answer:
Coefficient of
is more than 4
Explanation:
Oxidation: 
- Balance charge:
......(1)
Reduction: 
- Balance Cr:

- Balance O and H in acidic medium:

- Balance charge:
.......(2)
gives balanced equation:

So coefficient of
is more than 4
When your substance either; change color, start to smell, explode, form bubbles, precipitate, and/or get hotter or colder.