04_02_ex_04.tex

{A circular balloon is inflated with air flowing at a rate of 10cm$^3$/s. How fast is the radius of the balloon increasing when the radius is:
	\begin{enumerate}
	\item		1 cm?
	\item		10 cm?
	\item		100 cm?
	\end{enumerate}
}
{\begin{enumerate}
\item	$5/(2\pi)\approx 0.796$cm/s
\item $1/(40\pi)\approx 0.00796$ cm/s
\item $1/(4000\pi)\approx 0.0000796$ cm/s
\end{enumerate}
}