Answer:
"1155 N" is the appropriate solution.
Explanation:
Given:
Acceleration,

Forces resisting motion,

Mass,

By using Newton's second law, we get
⇒ 
Or,
⇒         
By putting the values, we get
⇒             
⇒             
⇒             
 
        
             
        
        
        
2nd and only 2nd option is right
        
             
        
        
        
Answer:
The sound intensity of train is 1000 times greater than that of the library.
Explanation:
We have expression for sound intensity level,
             
A train whistle has a sound intensity level of 70 dB
We have
            
A library has a sound intensity level of about 40 dB
We also have
            
Dividing both equations
            
The sound intensity of train is 1000 times greater than that of the library.
 
        
             
        
        
        
Weow that’s cool but what is your question
        
             
        
        
        
The answer is the last option.