Answer
11.5 m
Work Step by Step
There is an interval of 67.0 ms between the end of one chirp and the beginning of the next.
In that time, the pulse travels to the moth and back to the bat.
In half that time, 33.5 ms, the pulse travels to the moth. Find the distance to the moth, d.
$$d=vt=(343m/s)(33.5\times10^{-3}s)=11.5m$$
