A geyser, operating on LPG (liquefied petroleum gas) heats water flowing at the rate of $3.0$ litres per minutes, from $27^{\circ} \mathrm{C}$ to $77^{\circ} \mathrm{C}$. If the heat of combustion of LPG is $40,000 \mathrm{~J} / \mathrm{g}$, how much fuel, in $\mathrm{g}$, is consumed per minute? (Specific heat capacity of water is $4200 \mathrm{~J} / \mathrm{kg}-\mathrm{K}$ )
(a) $15.25$
(b) $15.50$
(c) $15.75$
(d) $16.00$