$A$ nucleus $_n{X^m}$ emits one $\alpha$ and one $\beta$ particle. The resulting nucleus is:

Consider the following two statements:
$A.$ The energy spectrum of $\alpha-$ particles emitted in radioactive decay is discrete.
$B.$ The energy spectrum of $\beta-$ particles emitted in radioactive decay is continuous.

$A$ radioactive nucleus emits a beta particle. The parent and daughter nuclei are

Which of the following physical quantities is measured using the unit $rad$?

An element $A$ decays into element $C$ by a two-step process:
$A \to B + {\;_2}He^4$
$B \to C + 2e^-$
Then:

The nucleus ${ }_{88}^{226} Ra$ is converted into ${ }_{82}^{206} Pb$ by the emission of alpha $(\alpha)$ and beta $(\beta)$ particles. The number of alpha and beta particles emitted are respectively: