A bear scratches his claws on a big pine tree. Does the bear do work on the tree? why or why not? (btw it has to do with physics) ITS NOT A GENERAL QUESTION.

The bear is actually sharpening his claws. That's the only reason he scratches a tree with his claws

Explanation:

answer: decibel

explanation:

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.