Manoj walks at an average speed of 4 km/hr. How long will it take for him to reach a distance of 1 mile ?

Question

$\begin{array}{1 1} (a)\; \text{4 hr} \\ (b)\; \text{0.25 hr} \\ (c)\; \text{0.4 hr} \\ (d)\; \text{2.5 hr} \end{array}$