Answer:
A turbine spins to generate electricity. There are many ways to spin the turbine by using water, steam, nuclear and so on.
How fine do you want them categorized for the ranking ?
What's the population to be ranked ?
The 4000 naked-eye-visible stars ?
The stars within, say, 50 light years from Earth ?
All 200-400 billion stars in the Milky Way galaxy ?
All the stars in some other galaxy ?
Or did you have a list of items to be ranked that you decided not to share ?
That would be a lot like asking us to seat a class of sixth graders alphabetically,
and then not telling us their names.
And how do we drag one star on top of another ?
And if I do that here, how will you know about it ?
Answer:
The climate of the earth throughout history has always been <em><u>fluctuated between hot and cold periods. </u></em>
Explanation:
(a) The period of a wave is the time required for one complete cycle. In this case, we have the time of five cycles. So:
(b) The frequency of a wave is inversely proportional to its period:
(c) The wavelength is the distance between two successive crests, so:
(d) The speed of a wave is defined as:
Answer it is b is the best option to pick A, does that make sense
