Answer:
The technique in which people use machines to learn how to control their bodies is known as D, Biofeedback.
Explanation:
Biofeedback is a variety of different machines that help people learn how to control their bodies depending on their specific needs, varying from things like scalp sensors, electrocardiographs, electromyographs and more.
 
        
                    
             
        
        
        
Period = 6 seconds and  .
 .
<u>Explanation:</u>
We have , the motion of a swing that requires 6 seconds to complete one cycle. Period is the amount of time needed to complete one oscillation . And in question it's given that 6 seconds is needed to complete one cycle. Hence ,Period of the motion of a swing is 6 seconds . Frequency is the number of vibrations produced per second and is calculated with the formula of   . SI unit of frequency is Hertz or Hz. We know that time period is 6 seconds so frequency =
 . SI unit of frequency is Hertz or Hz. We know that time period is 6 seconds so frequency =    
 
⇒ 
⇒ 
⇒ 
Therefore , Period = 6 seconds and  .
 .
 
        
             
        
        
        
Answer:
E=-1.51 eV.

Explanation:
The nth level energy of a hydrogen atom is defined by the formula,

Given in the question, the hydrogen atom is in the 3p state.
Then energy of n=3 state is,

Therefore, energy of the hydrogen atom in the 3p state is -1.51 eV.
Now, the value of L can be calculated as,

For 3p state, l=1

Therefore, the value of L of a hydrogen atom in 3p state is  .
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