Over a 200-year period, a volcano erupted once. according to this information, what is the yearly frequency of volcanic eruption? a. 99% b. 20% c. 0.5% d. 1%

C 0.5 percent is the answer this is because 1 is .5 percent of 200.

The answer cannot be A because this would mean there were 198 eruptions.
It cannot be B because this would mean there were 40 eruptions.
It cannot be D because this would mean there were 2 eruptions.

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