A gas based geyser heats water flowing at the rate of $5.0$ litres per minute from $27^\circ\text{C} \text{ to } 87^\circ\text{C}$. The rate of consumption of the gas is ____ g/s. (Take heat of combustion of gas = $5.0 × 104J/g$) specific heat capacity of water = $4200 J/kg. °C$