Rahul walks 6 km in 2 hrs and rests for 30 minutes. Again he walks in the same direction for another 3 km in 1 hr. What is the average speed Rahul walked in during his entire travel?

Question

$\begin{array}{1 1} (a)\; 1 \; km/hr\\ (b)\; 2\; km/hr \\ (c)\; 3 \;km/hr \\ (d)\; 2.5\; km/hr \end{array}$