Answer:
8h+100
8.50h+80
Step-by-step explanation:
 
        
             
        
        
        
For this case we have the following multiplication:
 
 We can rewrite this multiplication in the following way:
 
 From here, we apply the distributive property.
 We have then:

 Therefore, Jack's strategy is:
 Write the number in an expanded form and then apply the distributive property.
 Answer:
 Jack's strategy is:
 Write the number in an expanded form and then apply the distributive property.
 
        
                    
             
        
        
        
I think B or A is the answer