The correct answer is d. 3.5 billion years.
Prokaryotes were the first forms of life on Earth long before simple multicellular life appeared because of their ability to withstand extreme conditions. It is believed that the first living forms were bacteria combined with archaea in the microbial mat (multi-layered sheet).
Answer:
Your answer is A) Emulsify Fats.
The answer is
C. Both systems help remove carbon dioxide from the body.
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