The answer would most likely be joking
Yellow Marrow is common in the skeleton in old age but not in a childhood skeleton.
The placenta, the umbilical cord, and the amniotic sac.
I think one of them is B I’m not sure for the other
The part of muscle that he needs to train is the Slow-twitch muscle fibers.
<h3>What are Slow-twitch muscle fibres?</h3>
The Slow-twitch muscle fibers are the muscle fibres that are used to support long distance endurance journey such as the marathon race.
Therefore, the part of muscle that he needs to train is the Slow-twitch muscle fibers.
Learn more about muscle here:
brainly.com/question/13920046
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