The fuel consumed by a motorcycle during a journey while traveling at various speeds is indicated in the graph below.
The distances covered during four laps of the journey are listed in the table below
$$\begin{array}{|c|c|c|} \hline \textbf{Lap} & \textbf{Distance} & \textbf{Average speed} \\ & \textbf{(kilometres)} & \textbf{(kilometres per hour)} \\ \hline \mathbf{P} & 15 & 15 \\ \hline \mathbf{Q} & 75 & 45 \\ \hline \mathbf{R} & 40 & 75 \\ \hline \mathbf{S} & 10 & 10 \\ \hline \end{array}$$ From the given data, we can conclude that the fuel consumed per kilometre was least during the lap
- $\mathrm{P}$
- $\mathrm{Q}$
- $\mathrm{R}$
- $\mathrm{S}$