Question

Two red and two overlapping balls in the center are surrounded by a green, fuzzy, circular cloud with a white line running through it. Two green balls sit on the white line, and a line leading a bracket around the balls is labeled A. A line leading to a bracket overlapping the white line is labeled B.
Which is a characteristic of the part of the atom marked "A”?

It contains most of the mass.
It is negatively charged.
It is mostly empty space.
It is composed of electrons

Answer 1

It contains most of the mass.

The part labeled A is the nucleus (protons and neutrons), which holds nearly all an atom’s mass. It is positively charged, not negative; the electrons (green) are outside in the mostly-empty electron cloud.