Explanation:
Area of a circle is:
A = πr²
Take derivative with respect to time:
dA/dt = 2πr dr/dt
Plug in values and solve:
-5 = 2π (2) dr/dt
dr/dt = -5/(4π)
dr/dt ≈ -0.398
The radius is shrinking at approximately 0.398 in/min.
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