Vince is baking a cake. he pours flour and sugar into an empty bowl. the substance in the bowl is a(n)
a)atom.
b)element
c)mixture.
d)compound.

c) mixture.

Explanation:

An atom is the smallest entity of any substance which consists of subatomic particles called as neutrons, protons and electrons.

An element is a pure substance which is  composed of atoms of similar elements. Example:  

Mixture is  formed when atoms of similar or different elements are mixed in no fixed ratio without any chemical combination.

A compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.  Example:

beta is electron from nucleus

something from nucleus has changed, but charge must be same for cons of charge