Advantage: It's often cleaner (better for the environment)
Disadvantage: The initial cost can be very expensive, the transition may also be difficult.
The magnetic field of a bar magnet is strongest at either pole of the magnet. It is equally strong at the north pole when compared with the south pole. The force is weaker in the middle of the magnet and halfway between the pole and the center.
The exact same amount of force will be exerted but in opposite direction
Escape velocity is the velocity an object needs to escape the gravitational influence of a body if it is in free fall, i.e. no force other than gravity acts on it. Your rocket is not in free fall since it is using its thruster to maintain a constant velocity so the notion of "escape velocity" does not apply to it.
A proton consists of 2 up quarks and 1 down quark.
A neutron consists of 1 up quark and 2 down quarks.
A deuterium nucleus consists of one proton and one neutron, so its quark composition is (3) 3 up quarks and 3 down quarks.