A 12.5-g bullet is fired into and embeds itself in a 2.47-kg block attached to a spring with a spring constant of 21.2 N/m and whose mass is negligible. How far is the spring compressed if the bullet has a speed of 270 m/s just before it strikes the block, and the block slides on a frictionless surface

kepler used the data from tycho blahe (his mentor) to construct the laws of planetary motion.

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.