12 hrs. 30-6 is 24/2 gives you 12
        
             
        
        
        
Answer:
 B :step 2   she didnt collect all the like terms and calculate 
Step-by-step explanation:
first rewrite  remove all (  )Parentheses 
2nd   collect all like terms and calculate 
a^4 + 7a -16 -12^a^3 + 5a -3 
a^4 + 12a - 19 - 12a^3     ( Like terms are 7a +5a  and -16 +-3) 
so she skipped the second step
 
        
             
        
        
        
Answer:
1 solution
Step-by-step explanation:
s² - 35 = -35
Add 35 to both sides: <em>s² = 0</em>
<em>s can only be 0, and 0 has no positives nor negatives</em>, so one number.
 
        
                    
             
        
        
        
Answer:
d. 130
Step-by-step explanation: