Identify the nuclide produced when plutonium-239 decays by alpha emission: 239/94Pu->4/2He+ Identify the nuclide produced when thorium-234 decays by beta emission: 239/90Th->0/-1e+ Identify the nuclide produced when fluorine-18 decays by positron emission:18/9F->0/1e+ Identify the nuclide produced when thallium-201 decays by electron capture: 201/81Tl+0/-1e->0/0radiation+?