(a(i))[1]
Determine the number of protons in one nucleus of iodine-131.
(a(ii))[1]
Determine the number of neutrons in one nucleus of iodine-131.
(b)[2]
State what a beta-particle is and what a gamma ray is.
(c)[3]
Calculate the mass of iodine-131 left in the sample after 24.0 days.