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A measure of the amount contained in or constituting a physical body.


A force that gravitation exerts upon a body equal to the mass of the body times the acceleration of gravity.


A factor or condition that is subject to change, especially one that is allowed to change in a experiment to test a hypothesis.


To verify or regulate a experiment by conducting a parallel experiment or by comparing to another slandered.


The outcome of a result or an act.


The distance from one point to another.


The science that deals with the material universe beyond the Earths atmosphere.


A expert in astronomy.


An arrangement of lenses, mirrors or both that collects light allowing direct observation on or photographic readings of distant objects.

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