A52.0-kilogram skateboarder does a trick on a half-pipe. during the trick, he reaches a speed of 8.90 m/s. the radius of the half-pipe ramp is 3.00 meters. what is the minimum centripetal force necessary to keep the skater on the ramp?

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.