The spherical grit particles, having a radius of $0.01$ mm and specific gravity of $3.0$, need to be separated in a settling chamber. It is given that

• $g=9.81 \: m/s^2$
• the density of the liquid in the settling chamber $=1000 \: kg/m^3$
• the kinematic viscosity of the liquid in the settling chamber $=10^{-6} \: m^2/s$

Assuming laminar conditions, the settling velocity (in mm/s, up to one decimal place) is __________