A. a bicycle chain is an example of a compound machine
That force DEcreases. This is a big part of the reason why the Earth attracts you with more force than Jupiter does.
If i'm wrong sorry but i think it is 24hrs
Answer:

Explanation:
Given data
Space vehicle speed=5425 km/h relative to earth
The rocket motor speed=81 km/h and mass 4m
The command has mass m
From the conservation of momentum as the system isolated

Since the motion in on direction we can drop the unit vector direction

Where M is the mass of space vehicle which equals to sum of the motors mass and command mass.
The velocity of the motor relative to the earth equals the velocity of the motor relative to command plus the velocity of the command relative to earth

Where Vmc is the velocity of motor relative to command
This yields

Substitute the given values
El unico que se es el del oxígeno: o2