<span>Compound Microscope
Compound microscope is commonly used in the schools and colleges.
It comes under the category of microscopes used in biology.
It has two lenses namely the objective lens and the ocular lens.
It provides a magnification of 1500X.
Eyepiece lens is of 10X or 15X power.
It is used to observe bacterial, protozoa, various cells, etc.
</span><span>Dissecting Microscope
It is also called stereo microscope.
Its magnification power is less than the other microscope.
It gives a 3 dimensional picture.
Due to the low magnifying power they are used to observe little bigger objects than other microscopes.
They are used in the surgeries, dissection, forensic science etc.</span>
        
             
        
        
        
Answer:
h - height
Explanation:
gravitational potential energy = m * g * h
m stands for mass. Mass doesn't change in physics
g stands for gravitational acceleration. It is a constant.
h stands for height. When the skater moves up and down the track the height from the ground changes. Therefore this variable does change.
 
        
             
        
        
        
C. Vestigial structure is the correct answer