I'd guess at valve B. more information about the interesting question would help.
The main job of conducting electricity is the power source.
Answer:

Explanation:
To solve this exercise it is necessary to take into account the concepts related to gravitational potential energy, as well as the concept of perigee and apogee of a celestial body.
By conservation of energy we know that,

Where,

Replacing


Our values are given by,





Replacing at the equation,


Therefore the Energy necessary for Sputnik I as it moved from apogee to perigee was 
What is the kinetic energy of the system after the collision?

How this is calculated?
Given:
Initial speed=
mass of rod=M
Let, Initial kinetic energy =
Final kinetic energy=
Moment of inertia =I
What is the moment of inertia?

What is the angular momentum?
By conservation of angular momentum,


We know that, the final kinetic energy is given by,

What is the kinetic energy?
- In physics, the kinetic energy of an object is the energy that it possesses due to its motion.
- It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity.
- Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes.
To know more about kinetic energy, refer:
brainly.com/question/114210
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