I came up with d and e as an answer
        
             
        
        
        
To get to the end of the trail it would take 2 hours because the walking back hours would be double the walking out rate, but it would still have to equal 6 hours. So walking out would be 2 hours and walking back would be 4 hours which makes the trail 8 miles long.
        
             
        
        
        
18-12+7
 6 + 7
13
Write an equation.
Subtract first- the customer buys 12 black neon tetra fish which means subtraction
addition- the store clerk puts in 7 more black neon tetra fish which means your gonna add 7
 
        
                    
             
        
        
        
Answer:
I think its 9 & 12 maybe?
Step-by-step explanation:
Depending on what grade this is, that might be correct but im not 100% sure