Air carrying particles of density $1800k\frac{g}{m^3}$ and an average diameter of $20m$ enters a cyclone at a linear velocity of $18\frac{m}{s}.$ The diameter of the cyclone is $600mm.$ Determine: $($i$)$ The approximate separation factor for this cyclone, $($ii$)$The fraction of the particles that would be removed from the gas stream.