The part of an
atom that
determines its
identity.

The number of protons in the nucleus

Explanation:

The number of protons in the nucleus of an atom is its atomic number. This is the defining trait of an element: Its value determines the identity of the atom. For example, any atom that contains six protons is the element carbon and has the atomic number 6, regardless of how many neutrons or electrons it may have.

there is none because earth is stationary and flat.

i wish i could but this one is weird give me abc and i can solve it.