Because radio waves can travel in space but sound waves cannot.
Answer:
1) Hence, the period is 0.33 s.
2) The amplitude is 10 cm.
Explanation:
1) The period is given by:

Where:
f: is the frequency = 3 bob up and down each second = 3 s⁻¹ = 3 Hz
Hence, the period is 0.33 s.
2) The amplitude is the distance between the equilibrium position and the maximum position traveled by the spring. Since the spring is moving up and down over a distance of 20 cm, then the amplitude is:
Therefore, the amplitude is 10 cm.
I hope it helps you!
Answer:
Uranus, Pluto, Neptune, Saturn , Jupiter, mars, Venus ,mercury and sun
The answer to this is Protostar.
This is a process where it is gathering mass from its parent molecular cloud. Its a very young star meaning, the star was now born.
Hope this helped :)
Have a great day