Good are free zones bad is car pollution ext.
        
                    
             
        
        
        
Answer:

Negative sign shows that velocity of the car is decreases at a constant rate 
Explanation:
We have given velocity of the car is decreases from 32 m /sec to 24 m/sec in 4 second
So initial velocity of the car u = 32 m /sec
And finally car reaches to a velocity of 24 m/sec
Time taken to change in velocity = 4 sec
So final velocity v = 24 m/sec
From first equation of motion v = u+at 
So 

Negative sign shows that velocity of the car is decreases at a constant rate 
 
        
             
        
        
        
C. electrical energy is transformed into light and heat energy
        
                    
             
        
        
        
Wave speed = (wavelength) x (frequency)
Wave speed = (3 m) x (15 Hz)
<em>Wave speed = 45 m/s</em>