<span>B. Controls: The known powders attributes are already studied, so the are used as control measures to compare with the findings in the experiment with the unknown powders.</span>
Answer:
c
Explanation:
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Answer:
emf = 15 * Area and if A is given in square meters, the units of the emf will be Volts
Explanation:
Assuming that the area of the loop of current (A) is known, the magnitude of the induced emf can be calculated using Faraday-Lenz's Law:

and if the area (A) is given in square meters, the emf will directly come in units of Volts.
If an object is at rest, then its distance doesn't change as time goes on.
On the graph, the points for each time are all at the same distance. They form a horizontal line.