Size Reduction and Material Handling

A hammer mill comminutes grain from an initial $80\%$ passing size $d_1 = 1000\text{ }\mu\text{m}$ to a product $80\%$ passing size $d_2 = 100\text{ }\mu\text{m}$. If Bond's work index of the grain is $W_i = 12.0\text{ kWh/t}$, the energy required to grind 1 tonne of grain in $\text{kWh}$ according to Bond's law ($E = 10 W_i \left[\frac{1}{\sqrt{d_2}} - \frac{1}{\sqrt{d_1}}\right]$, where $d_1, d_2$ are in $\mu\text{m}$) is ________ (round off to 2 decimal places).