Correct: The sun is the center of the solar system. It is mostly gas. It is the most massive object in the solar system.
Atom
Molecule
Organelle
Cell
Tissue
Organ
Organ system
Organism
Explanation:
<em><u>risky </u></em><em><u>behavior </u></em><em><u>and </u></em><em><u>abuse </u></em>
Mutualism is where both animal help each other to benefit form each other. Win-Win . Commensalism is where nothing happen neither animal benefits from it .
