The decay constant of a radioactive substance is `0.693` per minute. What will be the half-life and mean life of it?

Explanation

To solve the problem, we need to find both the half-life and the mean life of a radioactive substance given its decay constant \( k = 0.693 \) per minute.

### Step 1: Convert the decay constant to per second
Since the decay constant is given in per minute, we should convert it to per second for easier calculations.

\[ k = 0.693 \, \text{per minute} = \frac{0.693}{60} \, \text{per second} \]
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