The radius of a circle is increasing at the rate of 0.7 cm/s. What is the rate of increase of its circumference?

Explanation

To solve the problem of finding the rate of increase of the circumference of a circle when the radius is increasing at a given rate, we can follow these steps:

### Step 1: Understand the relationship between radius and circumference
The circumference \( C \) of a circle is given by the formula:
\[ C = 2\pi r \]
where \( r \) is the radius of the circle.
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