Question $2$:

Water $($A$)$ drop $($spherical$)$ at $25C$ is suspended in still air $($assumed completely dry$)$ by a fine wire at $1\mathrm{.}01{10}^5.$ Its initial radius was $r_0=4mm.$

A$.$ Determine the time of complete evaporation of the water drop.

B$.$ After $1$ hour, what will be the radius of the drop. Determine the percentage of the initial water evaporated.

Data: Assume $p_{BM}$~$=1.$ Water density $=997k\frac{g}{m^3}$ Area, $A=4r^2$; Volume,$V=(\frac{4}{3})r^3$; Mass $=V$