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.
The time period for guilty party was between 1900-1988.
I think the correct answer from the choices listed above is the first option. In order for a person to "see" an object, light waves pass through the cornea. The cornea is the transparent layer forming at the front of the eye. Hope this answers the question. Have a nice day.
B. <span>10,824 feet
is the right answer
tan 26 = 6000/x
x = 10824 ft</span>