False, it states that matter can be nether created nor destroyed 
 
        
                    
             
        
        
        
Argon is a suitable choice for light bulbs because it's inert. Compared to a reactive gas like oxygen, the metal filimant would burn up in a reactive  enviroment, which is why a noble gas is used.
        
             
        
        
        
Answer:
Relative motion of source and observer.
Explanation:
Doppler Effect : It is the change in the observed frequency of the wave due to<em><u> relative motion of the source and object </u></em>.
 
        
             
        
        
        
Answer:
A hot spot is an area on Earth over a mantle plume or an area under the rocky outer layer of Earth, called the crust, where magma is hotter than surrounding magma. The magma plume causes melting and thinning of the rocky crust and widespread volcanic activity.
Hope this is what you mean be hot spot!
I hope this helps you!  
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