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The half-life of a radioactive nuclide is 20 hrs. The fraction of the original activity that will remain after 40 hrs is ______.

#### Options

1/8

1/2

1/4

1/6

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#### Solution

The half-life of a radioactive nuclide is 20 hrs. The fraction of the original activity that will remain after 40 hrs is **1/4**.

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