The diameter of a circular park is 30 m. Find its surface area.

Explanation

To find the surface area of a circular park with a diameter of 30 meters, we can follow these steps:

### Step 1: Find the radius of the circular park
The radius (r) is half of the diameter. Given that the diameter is 30 meters:
\[ r = \frac{\text{diameter}}{2} = \frac{30 \, \text{m}}{2} = 15 \, \text{m} \]

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