It would be the muscles because their contracting and forcing the blood back to the heart
Friction always opposes motion.
<span>Whether it be through air resistance, or simple surface friction, the speed of a moving body always decreases when some frictional force acts on it. For objects sliding on a surface, friction is less than for objects at rest on the same surface
please mark as brainliest
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<span> B. plutonic. An intrusive igneous rock is also known as plutonic</span> and has large crystals from slow-cooling magma. Types of intrusive rocks include gabbro, granite, dunite and diorite.
