Answer:
its letter b 
Explanation:
it represents the spectrum of stars 
 
        
             
        
        
        
Answer:
True
Explanation:
Yes I agree object can be in motion and in not motion at the same time for example there are two men travelling on the bus one person is A another person is B. the person be B rest so by seeing person be the person A also sits but the person see who saw the person be B move along with person C so the the person be B is in rest for person Abut is motion for a person C.
 
        
             
        
        
        
Answer:
(D) chlorine has a greater ionization energy than sodium
Explanation:
Sodium is the element of the group 1 and period 3 which means that the valence electronic configuration is ![[Ne]3s^1](https://tex.z-dn.net/?f=%5BNe%5D3s%5E1) .
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Chlorine is the element of the group 17 and period 3 which means that the valence electronic configuration is ![[Ne]3s^23p^5](https://tex.z-dn.net/?f=%5BNe%5D3s%5E23p%5E5) .
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Ionization energy is the minimum amount of energy which is required to knock out the loosely bound valence electron from the isolated gaseous atom.
<u>Thus, removal of one electron in sodium is easy as it will gain noble gas configuration and become stable. But this case does not exist in chlorine and hence, chlorine has a greater ionization energy than sodium.</u>
So, 
Sodium is much more apt to exist as a cation than chlorine because chlorine has a greater ionization energy than sodium.
 
        
             
        
        
        
Answer:
Na+Cl2-----NaCl
Explanation:
it's the chemical formula of common salt.