The answer is C) A girl hangs by both hands, motionless, from a trapeze.
An object in motion will continue to move in the same direction and with the same speed unless acted upon by an unbalanced force. states that forces occur as equal and opposite pairs. The strength of the force is related to the mass of the objects and the distance between them.
Answer:
A) 
B) 
C) 
D) mosquitoes speed in part B is very much larger than that of part C.
Explanation:
Given:
- Distance form the sound source,

- sound intensity level at the given location,

- diameter of the eardrum membrane in humans,

- We have the minimum detectable intensity to the human ears,

(A)
<u>Now the intensity of the sound at the given location is related mathematically as:</u>
..........................................(1)



<em>As we know :</em>


is the energy transferred to the eardrums per second.
(B)
mass of mosquito, 
<u>Now the velocity of mosquito for the same kinetic energy:</u>



(C)
Given:
- Sound intensity,

<u>Using eq. (1)</u>



Now, power:



Hence:




(D)
mosquitoes speed in part B is very much larger than that of part C.
-is made mostly of hydrogen and helium.
-will eventually run out of fuel and die.
-creates energy through nuclear reactions