The answer is theory because it says if and that means theory
        
             
        
        
        
Answer:
a. BH₃
Explanation:
According to the octet rules, atoms reach stability when are surrounded by eight electrons in their valence shell when they combine to form a chemical compound.
From the options, the only compound in which the central atom does not meet the octet rules is BH₃. The central atom is boron (B), which has 3 electrons in its valence shell. When B is combined with hydrogen (H), 3 electrons from the 3 atoms of H are added. The total amount of electrons is 6, fewer than 8 electrons needed to meet the rule.
hope this helps 
 
        
             
        
        
        
Answer:
there are two significant figures is the number 8400
Explanation:
 
        
                    
             
        
        
        
Answer:
positively charged elctrons
 
        
                    
             
        
        
        
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You can do it on the icing of roads, reverse osmosis for desalination of water, dissolved CO2 in soda cans, osmotic pressure involving blood vessels and IV solutions, etc.</span>