As a result of osmosis,what happens to the volume of the solution?

Identify the pair of solutions that exhibits the same osmotic pressure. [Molar mass of urea $= 60 \text{ g mol}^{-1}$ and molar mass of glucose $= 180 \text{ g mol}^{-1}$]

$50 \ mL$ of $0.2$ molal urea solution (density $= 1.012 \ g \ mL^{-1}$ at $300 \ K$) is mixed with $250 \ mL$ of a solution containing $0.06 \ g$ of urea. Both the solutions were prepared in the same solvent. The osmotic pressure (in Torr) of the resulting solution at $300 \ K$ is . . . . . $[\Delta_{mix} V = 0]$

The osmotic pressure of a solution containing $3 \ g$ of glucose (molar mass = $180 \ g/mol$) in $60 \ g$ of water at $15^\circ C$ (density = $1 \ g/mL$) is ....... $atm$.

Solution $A$ is prepared by dissolving $1 \text{ g}$ of a protein (molar mass = $50000 \text{ g mol}^{-1}$) in $0.5 \text{ L}$ of water at $300 \text{ K}$. Its osmotic pressure is $x \text{ bar}$. Solution $B$ is made by dissolving $2 \text{ g}$ of the same protein in $1 \text{ L}$ of water at $300 \text{ K}$. The osmotic pressure of solution $B$ is $y \text{ bar}$. The entire solution of $A$ is mixed with the entire solution of $B$ at the same temperature. The osmotic pressure of the resultant solution is $z \text{ bar}$. $x, y$ and $z$ respectively are: $(R = 0.083 \text{ L bar mol}^{-1} \text{ K}^{-1})$

If $5\%$ sugar solution is isotonic with $1\%$ solution of unknown substance,then find out the molecular mass of the unknown substance. (in $g/mol$)