Answer:
When you don't move, you still use energy. This energy is called potential energy, or, stored energy.
When you don't move or do work, you can use energy.
Answer:
0.78 m
Explanation:
The relationship between wavelength and frequency of a wave is given by

where
v is the speed of the wave
f is the frequency
is the wavelength
For the sound wave in this problem, we have
is the frequency
v = 344 m/s is the speed of sound in air
Substituting into the equation and re-arranging it, we find the wavelength:

B explanation : they are both filled to the same pint
Explanation:
Lasers produce a narrow beam of light in which all of the light waves have very similar wavelengths. The laser's light waves travel together with their peaks all lined up, or in phase. This is why laser beams are very narrow, very bright, and can be focused into a very tiny spot.
5.4 x 1014Hz
wavelength x frequency = the speed of light