Pllllllsssssssssss helpppp Determine the Mass Number of the Following Elements:
Al - 13 Protons 15 Neutrons

B - 5 Protons 6 Neutrons

C - 6 Protons 8 Neutrons

Sc - 21 Protons 25 Neutrons

Na - 11 Protons 13 Neutrons