8a+12b because you multiply 2 by each number. For example 4a times 2 is 8a and 6b times 2 is 12b
Hope that helped :)
        
             
        
        
        
Answer:
756.29
Step-by-step explanation:
2.04 x 105 = 214.2
and 9.07 x 107 = 970.49
970.49 - 214.2 = 756.29
 
        
             
        
        
        
I suppose its 7, subtracted