Long time ago, people saw the constellations as patterns in the sky.  They names these patterns and tell stories about them. What people saw laong time ago are just mere patterns which forms animals and shapes.  We got the names of our constellations from the Greeks who named the constellations after the mythological heroes and mythological legends.
        
                    
             
        
        
        
The greenhouse effect is a warming effect caused by certain gases that retain heat from sunlight. Without such gases, the average surface temperature of the Earth would be below freezing, and as explained by the Encyclopedia of Environmental Science, “life, as we know it, would not exist.” 
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 The global warming debate is centered upon whether added greenhouse gases released by human activity will overheat the Earth and cause harmful effects.</span><span>
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Answer:
 Yes such a frame exists: a free-fall (free-float frame) frame. This frame of reference is subject only to gravity and no forces such as electromagnetic forces or nuclear forces.
 
        
             
        
        
        
Answer: the expanding universe
Explanation:
Hope that helps!
 
        
             
        
        
        
The answer is definitely C.) their molecules move at the same average speed