An ordinary egg can be approximated as a $5\mathrm{.}5-cm-$diameter sphere whose properties are roughly $k=0\mathrm{.}6\frac{W}{m}*K$ and $=0\mathrm{.}14{10}^{-6}\frac{m^2}{s}.$ The egg is initially at a uniform temperature of $4C$ and is dropped into boiling water at $97C.$ Taking the convection heat transfer coefficient to be $h=1400\frac{W}{m^2}*K,$ determine how long it will take for the center of the egg to reach $72C.$ Solve this problem using the analytical one$-$term approximation method.

The time required is $$ min.