The simple capillary viscometer in Example $6\mathrm{.}2$ is not the same as that actually

used. In the practical versions, there are two marks on the glass, and the user

reads the time for the fluid level to pass between the two marks. In Example $6\mathrm{.}2,$

if the upper reservoir has a diameter of $10$ mm$,$ how many seconds does it take

the level in the reservoir to fall from $0\mathrm{.}02$ to $0\mathrm{.}01$ m$?$