Which of the following has the maximum penetrating power?

$C_{6}H_{5}F^{18}$ is an $F^{18}$ radio-isotope labelled organic compound. $F^{18}$ decays by positron emission. The product resulting from the decay is:

Radioactive substances emit $\gamma$-rays,which are

After the emission of an $\alpha$-particle from the atom $_{92}X^{238}$,the number of neutrons in the resulting atom will be:

An atom has a mass number of $232$ and an atomic number of $90$. How many $\alpha$-particles should it emit after the emission of two $\beta$-particles,so that the resulting atom has a mass number of $212$ and an atomic number of $82$?

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: