During the emission of a $\beta$-particle,what happens to the nucleus?

The radionuclide $_{90}^{234}Th$ undergoes two successive $\beta$-decays followed by one $\alpha$-decay. The atomic number and the mass number respectively of the resulting radionuclide are

The number of $\alpha$ and $\beta$-particles emitted in the nuclear reaction $_{92}U^{238} \to _{90}Th^{234} \to _{91}Pa^{234}$ are respectively:

If a radioactive isotope with atomic number $A$ and mass number $M$ emits an $\alpha$-particle,the atomic number and mass number of that new isotope will become:

$\beta$-particles are emitted from the atom

$A$ radioactive atom $^X_Y M$ emits two $\alpha$ particles and one $\beta$ particle successively. The number of neutrons in the nucleus of the product will be