Answer:
Resistor
Explanation:
Resistor provides resistance to the flow of electric current in a circuit. 
It controls the amount of current in a circuit by acting as a barrier to the flow of electric charges 
 
        
                    
             
        
        
        
Answer:
20m/second
Explanation:
The reason the answer is 20m/second is because to find the speed of the ball  in this question you have to divide the distance over the time giving you the result of 20m/second
 
        
             
        
        
        
The answer would be B.
(V=IR, 12-10i, 12/10=1.2)
        
             
        
        
        
The answer is:
d) the sound originates from a vibration.
The explanation:
The sound waves are generated by a sound source, such as the vibrating diaphragm of a stereo speaker. The sound source creates vibrations in the surrounding medium. As the source continues to vibrate the medium, the vibrations propagate away from the source at the speed of sound, thus forming the sound wave.