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Which one of the following nuclei has shorter meant life?

#### Options

C

A

Same for all

B

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#### Solution

**A**

**Explanation:**

The activity of such nuclei is determined by the slope of the supplied curves. In addition, the mean lifetime is inversely proportional to activity. As a result, the longer the activity, the shorter the substance's mean life. Nucleus A has the steepest slope. As a result, nucleus A has the shortest mean life of the three.

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