The initial concentration of a radioactive substance is No and its half life is 12 hours. What will be its concentration after 36 hours?

Explanation

To solve the problem of determining the concentration of a radioactive substance after a certain period, we can follow these steps:

### Step-by-Step Solution:

1. **Identify Given Values**:
- Initial concentration of the radioactive substance: \( N_0 \)
- Half-life of the substance: \( t_{1/2} = 12 \) hours
- Time elapsed: \( t = 36 \) hours
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