54) although neptune is the farthest planet from the sun, it travels in a fixed orbit around the sun and never changes its path. what is the reason for this? a) the magnetic pull of the sun holds neptune in its orbit. b) the gravitational pull of the sun holds neptune in its orbit. c) the nuclear force acting between the sun and neptune holds the latter in its orbit. d) the repulsive force of bodies outside the solar system holds neptune in its

answer;

d. are made mostly of liquid

explanation;

-the general   composition and structure planets includes; they have a thick gas and liquid layer covering a small,solid core. mostly the gases are hydrogen and helium atmosphere and layers of liquid hydrogen. for instance neptune and uranus are examples of the outer planets, they have a core covered by ice and ammonia.

-neptune's atmosphere is hydrogen and helium with a bit of methane so there is no oxygen to breath and the interior is made up of frozen water and ammonia with a rock and iron core. thus, there is no liquid water or solid surface to survive.