Answer:
2 
Step-by-step explanation:
 
        
                    
             
        
        
        
Search up heating curve chemistry: it should look somewhat like that lol :). But, the last interval should have a small slope, the middle interval a big slope, and the first interval: a medium slope.
        
                    
             
        
        
        
Answer:

Step-by-step explanation:
Simplify:
   45 = 5 * 3 * 3
   60 = 5 * 3 * 2 * 2
GCF = 5*3 = 15
            
                      
 
        
                    
             
        
        
        
B dhs.3200
because 10% of 4000=400
20%=800
4000-800=3200