An object is placed at some distance from a radio station. If the interval between transmission and reception of pulses is $2.66 \times 10^{-2}\: sec$, then the distance is:

Question

$\begin {array} {1 1} (a)\;4000\: km & \quad (b)\;2000\: km \\ (c)\;3000\: km & \quad (d)\;2500\: km \end {array}$