Answer:
If you apply a force to separate 2 opposite poles, the potential energy of the system increases.
Answer:
to know what that specif animal or thing does in the food chain
Explanation:
Your teacher is right. The moon can be seen early in the morning sometimes and late at night. Different phases are only visible on certain days as one day might be full quarter, the next full moon, the next first quarter, etc.
Answer:
Frequency, 
Explanation:
Wavelength of a light wave is 450 nm. It is required to find the frequency of this light wave. The speed of light is given by c. So,

f is the frequency of this light

So, the frequency of this light is
.
Liquid water because if it said very high then it would be water vapor but it didn’t say that so the answer is B liquid water