An alpha particle has an atomic mass of
1 amu
2 amu
3 amu
4 amu

4 amu

Explanation:

Rutherford verified that the alpha particle is a set of two protons and two neutrons, that is, it is the nucleus of the helium atom. It has an electric charge equal to + 2e, and a mass of 4.002764 units of atomic mass (amu), that is, almost 4 times the mass of the hydrogen atom.

luster is not a good characteristic to use by itself because luster is the property of minerals that indicates how much the surface of a mineral reflects light. the luster of a mineral is affected by the brilliance of the light used to observe the mineral surface.