Suppose you have a container filled with iron and sand. you can separate the iron from the sand if you so this is a
a) use a magnet; mixture.
b) melt the sand; mixture.
c) add baking soda; chemical compound.
d) dissolve the sand in water; solution.

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.

it's a b and