B) 4Na + O₂ → 2Na₂O
b) H₂ + Cl₂ ---> 2HCi
        
                    
             
        
        
        
You only need two numbers to do that.
The numbers are  16  and  -3 .
           16  -  3  =  13
         (16) x (-3)  =  -48 
        
             
        
        
        
Im gonna take an educated guess on this. for the first part only one element has an outershell filled completely. but if they want two elements put chlorine. to lose electrons is probably helium to gain is magnesium. and the last one is lithium and helium because they're small and don't have allot of atomic mass
        
             
        
        
        
It will be D. because you have to add the like terms which is 13 + 5 which will be 18 and so 10p doesn't have no like terms it just stays the same so it will be 10p+18
        
             
        
        
        
Answer:
68
Step-by-step explanation:
12 + 5 = 17
17 x 4 = 68
Andrea's monthly allowance is $68.