Given that,
Frequency emitted by the bat, f = 47.6 kHz
The speed off sound in air, v = 413 m/s
We need to find the wavelength detected by the bat. The speed of a wave is given by formula as follows :

or

So, the bat can detect small objects such as an insect whose size is approximately equal to the wavelength of the sound the bat makes i.e. 8.67 mm.
My guess is A. I'm not 100% positive but i'm pretty sure.
The answer is D
<em>"</em><em>a property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force.</em><em>"</em>
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