The radiations having high penetrating power and not affected by electrical and magnetic field are

The $_{88}Ra^{226}$ is

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:

The number of $\alpha$ and $\beta$-particles emitted in the nuclear reaction $_{90}^{228}Th \to _{83}^{212}Bi$ are respectively:

The substance used in cancer therapy is

Which statement is incorrect?