Which of the following compounds decompose on heating?

Which of the following orders are correct?
$(I)$ Thermal stability: $BeSO_4 < MgSO_4 < CaSO_4 < SrSO_4$
$(II)$ Basic nature: $ZnO > BeO > MgO > CaO$
$(III)$ Solubility in water: $LiOH > NaOH > KOH > RbOH$
$(IV)$ Melting point: $NaCl > KCl > RbCl > CsCl > LiCl$

Match List-$I$ with List-$II$:

List-$I$	List-$II$
$A$. $Na_2CO_3 \cdot 10H_2O$	$I$. $Caustic \ soda$
$B$. $NaOH$	$II$. $Slaked \ lime$
$C$. $Ca(OH)_2$	$III$. $Baking \ soda$
$D$. $NaHCO_3$	$IV$. $Washing \ soda$

Match the following substances in List-$I$ with their uses in List-$II$:
| List-$I$ (Substance) | List-$II$ (Use) |
| :--- | :--- |
| $(A)$ $Na_2O_2$ | $(I)$ Photoelectric cells |
| $(B)$ $D_2O$ | $(II)$ Antacid |
| $(C)$ $Cs$ | $(III)$ Oxidising agent |
| $(D)$ $Mg(OH)_2$ | $(IV)$ Moderator |

In which of the following are the $s$-block elements arranged in the correct order of their melting points?

Zeolites are