Which of the following elements shows a high tendency to form peroxide?

Which property of alkaline earth metals increases with their atomic number?

Select the correct statement from the following.

The order of thermal stability of carbonates of $IIA$ group is

Match the following alkaline earth metals with their respective densities $(g/cm^3)$:

$A$. $Be$	$I$. $1.74$
$B$. $Mg$	$II$. $1.84$
$C$. $Ca$	$III$. $2.63$
$D$. $Sr$	$IV$. $1.55$

$A$ metal $M$ readily gives $MSO_4$, which is soluble in water. It forms its oxide $MO$ which is amphoteric. It forms an insoluble hydroxide $M(OH)_2$, which is soluble in $NaOH$ solution. The $M$ is