Answer:
A. Different volumes of water are moved different distances.
Step-by-step explanation:
Integration is used to find work required to pump water out of a tank because different volumes of water are moved different distances and to sum it all we the tool required is integration. Moreover, work done is a path function or an inexact differential. It does depend upon the path followed by the process. 
hence the correct answer is A. 
 
        
             
        
        
        
Answer:
135
Step-by-step explanation:
15x18/2=135
..........
 
        
             
        
        
        
Answer:
-1
Step-by-step explanation:
 
        
             
        
        
        
Answer:
The redaction does not explain the situation.  If we assume that 15 balloons were used to make one ballon poodle and three giraffes, then the answer would be 7,5 balloons for 1 poodle, and 2,5 balloons for a giraffe
Step-by-step explanation:
With 15 balloons we make 1 poodle and 3 giraffes.  This means that 7,5 balloons were used to make 1 poodle, and other 7,5 balloons were used to make 3 giraffes.
If we divide   7,5 balloons between 3, we obtain 2,5.  This means that with 2,5 balloons we make 1 giraffe
 
        
             
        
        
        
Answer:
59
Step-by-step explanation:
2x+2 = 120 because they are vertical angles
2x = 118
x = 59