Answer:
To know if it is a function see if there are two of the same x-intercept( which makes a vertical line). If there is,then it is not a function.
 
        
                    
             
        
        
        
Answer:
if the cubes were hidden, but I belive the answer is none
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
60 grams sugar for 15 biscuits.
3x60 grams of flour, so 180 grams for 15 biscuits. 
60÷15= 4 batches.
4 batches with 180 grams each- 4 x 180= 720 grams of flour.