200 g of water is heated and its temperature goes from 280 k to 300 k. what is the mass?
a. 200 g
b. 200 kg
c. 200 n
d. 20 g

You just told us that it's 200g of water. So it doesn't matter what happened to it. If you were telling us the truth right at the beginning of the question, then the mass of the water is 200g.

so here is the information for current research:

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-resources of geothermal energy range from the shallow ground to hot water and hot rock found a few miles beneath the earth's surface, and down even deeper to the extremely high temperatures of molten rock called magma

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when heated, the valance electrons increased their speed and transferred the heat from electron to electron.   i just took the test.