What is the mass number?
A.the sum of the protons and electrons
B.the sum of the neutrons and electrons
C.the sum of the protrons and neutrons
D.the sum of the neutrons, protons and electrons
Answer:C
What is the mass number?
A.the sum of the protons and electrons B.the sum of the neutrons and electrons C.the sum of the protrons and neutrons D.the sum of the neutrons, protons and electrons