Which statement below is not true? A. The nucleus is positively charged because of the protons.

B. The positively and negatively charged subatomic particles determine the atomic mass of an atom.

3.A neutral atom will contain the same number of electrons as protons.

4.Neutrons are not charged particles, are found in the nucleus and have a mass of 1
amu.

what is the average time it took the car to travel 0.25 meters?

⇒ 2.23 seconds

what is the average time it took the car to travel 0.50 meters?

⇒ 3.13 seconds

what is the question here. i think you messed up.

ca has a crystalline lattice with positive ions (since it is a metal, metals are positively charged) and electrons flow freely in its structure since the ca atoms have a large nuclear radius so the electrons are not tightly held, therefore the electrons can flow freely since they are not being highly attracted by the nucleus. moreover, one of the properties of metals are that they are conductors of electricity, thus proving ca is the element.