I haven't worked on Part-A, and I don't happen to know the magnitude of the gravitational force that the Sun exerts on the Earth.
But whatever it is, it's exactly, precisely, identical, the same, and equal to the magnitude of the gravitational force that the Earth exerts on the Sun.
I think that's the THIRD choice here, but I'm not sure of that either.
The wavelength is related to the frequency by the relationship:

where v is the wave speed and f is its frequency.
The speed of sound in air is v=344 m/s. The lowest frequency is f=20.0 Hz, so the corresponding wavelength is

The highest frequency is

, so the corresponding wavelength is

Therefore, the range of wavelengths of audible sound in air is
[0.017 m - 17.2 m]
False because friction will generate heat energy and/or sound energy etc. Think of a car stopping or a broom sweeping the ground.
<span>It is important to determine their location before operating on an unfamiliar body of water because they are often difficult to spot, even with local charts. If you don't know what you're doing you can get stuck and that can be a huge problem, so it's necessary to know what you're doing and where they are located.</span>