A jet stream forms high in the upper troposphere between two air masses<span> of very different temperature. The greater the temperature difference between the air masses, the faster the wind blows in the jet stream.
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So "Differences in temperature between two air masses" is the answer
Answer:
The Hypothesis is a prediction based on the theory being tested.
The evidmence can support the Hypothesis or invalidate the Hypothesis.
Explanation:
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).