Thorium-232 absorbs a neutron in the first stage in a series of nuclear reactions that end in a nucleus Z\text{Z}Z.
90232Th+n→X ^{232}_{90}\text{Th} + \text{n} \rightarrow \text{X} 90232Th+n→X X→Y+β−+νˉe \text{X} \rightarrow \text{Y} + \beta^- + \bar{\nu}_{\text{e}} X→Y+β−+νˉe Y→Z+β−+νˉe \text{Y} \rightarrow \text{Z} + \beta^- + \bar{\nu}_{\text{e}} Y→Z+β−+νˉeHow many neutrons does Z\text{Z}Z have?
141
142
143
233
