Answer:
A) Propagation of pressure fluctuations in a medium
B) air is the medium in which the wave is transported,
Explanation:
Part A.
A sound wave is a longitudinal oscillation of the molecules that forms in a material medium, they can be solid, liquid or gases, therefore the wave propagates in the same direction as the oscillation of the particles.
The most correct answer is:
* Propagation of pressure fluctuations in a medium
Part b
air is the medium in which the wave is transported, otherwise it cannot propagate
Make Neptune closer to the sun because then it would have a stronger gravitation pull. Because the closer the objects are, they will have a stronger gravitaional force and when the object has more mass, the gravity is also stronger. So, if the mass is reduced, the gravity force would be reduced, but if you bring neptune closer, the gravity force would increase
Answer:
Range of wavelength will be
to 
Explanation:
We have given range of frequency is 400-560 Hz
Speed of the light 
We have to find the range of the wavelength of signal transmitted
Ween know that velocity is given by
, here
is wavelength and f is frequency
So for 400 Hz frequency wavelength will be 
And wavelength for frequency 560 Hz 
So range of wavelength will be
to 