Answer:
Period of brightness variation and luminosity.
Explanation:
The Cepheid variables are used as distance indicators. This requires estimation of periods and (usually) intensity-mean magnitudes in order to establish a period—apparent luminosity relation. It is particularly important for the techniques employed to be as accurate and efficient as possible.
<span>Force = Work done / distance = 4Nm / 2m = 2N</span>
In order to find total magnification of a microscope, you need to multiply the power of eyepiece and objective lens.
Hope this helps!
