The mass of an electron is A) equal to the mass of a proton B) less than the mass of a neutron C) greater than the mass of a proton D) equal to the mass of a neutron

B

Explanation:

Atomic structure contains electrons, protons and neutrons.

Electron is very light compared to proton and neutrons.

Given that the mass of an electron is

A) equal to the mass of a proton

B) less than the mass of a neutron

C) greater than the mass of a proton

D) equal to the mass of a neutron

The correct answer is B which is less than the mass of the neurons.

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.