The gross energy requirement, to reduce a very large feed of coal to such a size that $80\%$ of the product passes through a $100 \ \mu\text{m}$ screen, is $13 \text{ kWh}$ per ton of feed. In a process, $250 \text{ tons h}^{-1}$ of coal is crushed. The range of feed sizes is such that $80\%$ of the feed passes through an opening of $100 \text{ mm}$. The product size range is to be such that $80\%$ of the product passes through an opening of $25 \text{ mm}$. According to Bond's law, which one of the following is the power consumption (in kW)?