Extra (1): A hair dryer bears the inscriptions(220V-1500W) a. What do these inscriptions mean?
b. What current would it carry in normal functioning?

See the answers below.

Explanation:

a)

The dryer plate indicates that the estimated power is 1500 [W] and operates connected to the mains with an electrical voltage of 220 [V]

b)

The electrical current is determined by the following expression:

where:

V = voltage = 220 [V]

I = current [amp]

P = power [W]

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.