Osmotic pressure of solution of glucose is $1.20 \mathrm{atm}$ and that of solution of cane sugar is $2.5 \mathrm{atm}$. The osmotic pressure of the mixture containing equal volumes of the two solutions will be:

${\mathrm{FeCl}}_3$ on reaction with ${\mathrm{K}}_4\left[\mathrm{Fe}(\mathrm{CN}{)}_6\right]$ in aqueous solution gives blue colour. These are separated by a semipermeable membrane AB as shown. Due to osmosis, there is

$0.04 \mathrm{M}$ solution of ${\mathrm{K}}_2{\mathrm{SO}}_4$ is isotonic with $0.1 \mathrm{M}$ solution of urea at the same temperature. The degree of dissociation of ${\mathrm{K}}_2{\mathrm{SO}}_4$ is