Answer: gases
Explanation: because gases move around freely and they would be the only one to make sense because solid are compacted together and liquid are not so fast at moving but gases are wild
dont use this this is a bad explanation
Answer:Reflection
Explanation:
The throwing back of a sound wave without absorbing it is called reflection
In acoustic reflection of sound is termed as echo i.e. sound arrived at the listener after a particular delay depending upon the position of barrier to the observer.
The reflection of sound is used in many devices like megaphone, trumpets, etc. It is also used in auditorium such that the ceiling of the auditorium is curved for multiple reflections of sound so that sound can be reached at every corner of the auditorium.
Answer:1.5×10 to the power of 17(unit-Hertz/H)
Explanation:V=F×Wavelength
F=V/Wavelength=3×10 to power/2×10 to power of -9=1.5×10 to power of 17
