The correct answer to your question here is D
Answer:
The speed will be "18km/s". A further explanation is given below.
Explanation:
According to the question, the values are:
Wavelength,



As we know,
⇒ 
On substituting the values, we get
⇒ 
⇒ 
⇒ 
⇒ 
or,
⇒ 
The wise and careful use of energy is called CONSERVATION
Answer:
turning a doorknob
Explanation:
it will snap back once you release it.
D. Power. The unit of power is watt.