Which of the following is not emitted during the radioactive decay of a radioactive element?

The radioactive nucleus $_7N^{13}$ decays to $_6C^{13}$ through the emission of

$A$ nucleus $_Z^AX$ emits an $\alpha$-particle. The resultant nucleus then emits a ${\beta ^ + }$ particle. What will be the respective atomic number and mass number of the final nucleus?

Alpha particles are

The nucleus $_{90}Th^{228}$ transforms into $_{83}Bi^{212}$. How many $\alpha$-particles and $\beta$-particles are emitted during this process?

The decay of a proton to a neutron is: