Draw a graph showing the variation of decay rate with number of active nuclei.

Explanation

To draw a graph showing the variation of decay rate with the number of active nuclei, follow these steps:

### Step 1: Understand the Relationship
The decay rate (dn/dt) is proportional to the number of active nuclei (n). This relationship can be expressed mathematically as:
\[ \frac{dn}{dt} \propto n \]
This means that as the number of active nuclei decreases, the decay rate also decreases.

### Step 2: Set Up the Axes
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