A nucleus of thorium-232 (90232Th\text{}^{232}_{90}\text{Th}90232Th) undergoes a series of radioactive decays, emitting four alpha particles and three beta-minus particles to become a stable isotope of astatine.
What are the nucleon number A A\,A and the proton number Z Z\,Z for the resulting astatine nucleus?
A=216,Z=85A = 216, Z = 85A=216,Z=85
A=216,Z=82A = 216, Z = 82A=216,Z=82
A=224,Z=85A = 224, Z = 85A=224,Z=85
A=216,Z=79A = 216, Z = 79A=216,Z=79
