$34.$ A fermentation broth of density $1000kg{m}^{-3}$ and viscosity ${10}^{-3}kg{m}^{-1}{s}^{-1}$ is mixed in a $100L$ fermenter using a $0\mathrm{.}1m$ diameter impeller, rotating at a speed of $2s^{-1}.$ The impeller Reynolds number is

Answer: $(20000$ to $20000)$