A family is visiting the Statue of Liberty in New York City. One of the children accidentally drops her backpack from the top of the viewing platform which is 300 feet above the ground. At what height will the kinetic energy of the backpack be equal to it's potential energy?

the bal will not change its velocity.

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.