The $\% \ w/V$ unit is used in which branch of science?

Molarity $(M)$ of an aqueous solution containing $x \ g$ of anhydrous $CuSO_4$ in $500 \ mL$ solution at $32^{\circ} C$ is $2 \times 10^{-1} \ M$. Its molality will be. . . . . .$\times 10^{-3} \ m$ (nearest integer). [Given density of the solution $= 1.25 \ g/mL$.]

Match List-$I$ with List-$II$.

List-$I$ (Example)	List-$II$ (Type of Solution)
$A$. Humidity	$I$. Solid in solid
$B$. Alloys	$II$. Liquid in gas
$C$. Amalgams	$III$. Solid in gas
$D$. Smoke	$IV$. Liquid in solid

Choose the correct answer from the options given below:

Which of the following modes of expressing concentration is independent of temperature?

Calculate the mole fraction of solute in the solution if the solution is prepared by dissolving $394 \ g$ of a nonvolatile solute in $622 \ g$ of water at $30^{\circ}C$ (Molar mass of solute $= 342 \ g \ mol^{-1}$).

Calculate the molarity of $NaOH$ solution prepared by dissolving $0.4 \ g$ of $NaOH$ in enough water to form $500 \ mL$ of the solution. (in $M$)