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3 years ago

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If humans originated in Africa and migrated to other parts of the world some time would be required for this to occur.At the mod

est rate of one kilometer per year, how many centuries would it take for humans originated in Africa to travel to China, some 10,000 kilometers away?

1 answer:

Thepotemich [5.8K]3 years ago

7 0

Answer:

100 years

Explanation:

10,000 divided by 100 equals 100

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Norma-Jean [14]

The power of the antenna is
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and since the power is the emitted energy divided by the time, the energy emitted per second is
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So the energy of a single photon is
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zheka24 [161]

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3 years ago

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Answer

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Explanation:

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