<span>Each second, solid sodium chloride dissolves and solid sodium chloride recrystallizes.
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<span>It can be inferred from atomic line spectra. These are certain wavelengths of light that atoms give off when they become excited. The energy levels in an atom can be proven to exist from this phenomenon, and furthermore, they can be measured.</span>
        
             
        
        
        
Can you give more information?
        
             
        
        
        
Answer:
D. VISCOSITY can be defined as a substance's ability to resist flow. 
Explanation:
This is the statement that correctly describe the term viscosity. Viscosity explains why substances or fluids resist flow. It shows that internal friction or resistance to flow revealed by a substance. A substance with high viscosity or internal friction resist flow and one with low viscosity flow easily. Viscosity of a substance change base on various factors affecting the substance such as pressure, temperature, surface area. Substances like water has low viscosity explaining why it flows easily. 
 
        
             
        
        
        
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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