If the radius of a sphere is measured as 9 cm with an error of 0.03 cm, find the approximate error in calculating its surface area.

Explanation

To solve the problem of finding the approximate error in calculating the surface area of a sphere when the radius is measured with an error, we can follow these steps:

### Step 1: Identify the given values
- The radius of the sphere, \( r = 9 \) cm
- The error in the radius, \( \Delta r = 0.03 \) cm

### Step 2: Write the formula for the surface area of a sphere
The surface area \( A \) of a sphere is given by the formula:
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