$($c$)$ The following data are given for a sedimentation tank:

Flow through velocity

Depth of water in the sedimentation tank $,=0\mathrm{.}9m$

Specific Gravity, Gs

$=0\mathrm{.}3\frac{m}{s}$

$=0\mathrm{.}9m$

$=2\mathrm{.}65$

Assuming that the Stokes Law is valid, determine the diameter of particles that

would be removed with a $100\%$ efficiency.

$(15$ Marks$)$