The decay of a proton to a neutron is:

Explain the $\alpha$-decay process and give its appropriate example.

Which of the following rays are not electromagnetic waves?

$A$ radioactive nucleus decays as follows:
$X \xrightarrow{\alpha} X_1 \xrightarrow{\beta} X_2 \xrightarrow{\alpha} X_3 \xrightarrow{\gamma} X_4$
If the mass number and atomic number of $X_4$ are $172$ and $69$ respectively,then the atomic number and mass number of $X$ are:

In the given reaction sequence ${ }_z X^A \rightarrow{ }_{z+1} Y^A \rightarrow{ }_{z-1} K^{A-4} \rightarrow{ }_{z-1} K^{A-4}$,identify the radioactive radiations emitted in order.

${ }_{82}^{290} X \xrightarrow{\alpha} Y \xrightarrow{e^{+}} Z \xrightarrow{\beta^{-}} P \xrightarrow{e^{-}} Q$
In the nuclear emission stated above, the mass number and atomic number of the product $Q$ respectively, are