The north pole of one magnet attracts the south pole of another magnet. The needle of a compass is itself a magnet; the end of the needle that points north is capped with an arrow and often painted red.
In light of this, explain why the arrow-capped end of a compass needle is attracted to the North Pole of the Earth.

a. The geographic North Pole is actually the south magnetic pole of the Earth.
b. The arrow-capped end of the compass needle is actually the south magnetic
pole of the compass needle.

d. air pressure decreases as altitude increases.

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.

higher potential

explanation:

because it is in a high speed so it must move into a of high potential

the doppler effect is used by weather forecasters to measure 

moving clouds