Which of the following pairs of solutions is expected to be isotonic at the same temperature?

Assuming complete ionisation,arrange the following solutions in order of increasing osmotic pressure.
$(a)$ $0.5 \ m \ Li_2SO_4$
$(b)$ $0.5 \ m \ KCl$
$(c)$ $0.5 \ m \ Al_2(SO_4)_3$
$(d)$ $0.1 \ m \ BaCl_2$

The concentration in $g/L$ of a solution of cane sugar $(M = 342)$ which is isotonic with a solution containing $6 \ g$ of urea $(M = 60)$ per litre is :-

Equal volumes of $0.2 \ M$ urea and $0.2 \ M$ glucose are mixed. The mixture will have

The osmotic pressure of a living cell is $12 \ atm$ at $300 \ K$. The strength of sodium chloride solution that is isotonic with the living cell at this temperature is $...... \ g \ L^{-1}$. (Nearest integer)
Given : $R = 0.08 \ L \ atm \ K^{-1} \ mol^{-1}$
Assume complete dissociation of $NaCl$
(Given : Molar mass of $Na$ and $Cl$ are $23$ and $35.5 \ g \ mol^{-1}$ respectively.)

$A$ solution in which red blood cells can remain in their normal form is called ......