Bats Can Detect Small Objects Such as Insects That Are

Bats can detect small objects such as insects that are of a size in the order of a wavelength. If bats emit a chirp at a frequency of 60 kHz and the speed of sound waves in air is 330 m/s, what is the smallest size insect they can detect?

A) 1.5 mm
B) 3.5 mm
C) 5.5 mm
D) 7.5 mm
E) 9.8 mm