Chemical Equilibrium Questions

A $20$ litre container at $400\text{K}$ contains ${\text{CO}}_2(g)$ at pressure $0.4\text{atm}$ and an excess of $\text{SrO}$ (neglect the volume of solid $\text{SrO}$). The volume of the container is now decreased by moving a piston. The maximum volume of the container, when pressure of ${\text{CO}}_2$ attains its maximum value, will be [Given: ${\text{SrCO}}_3(s)\rightleftharpoons \text{SrO}(s)+{\text{CO}}_2(g)$, $K_p=1.6\text{atm}$ ]:

The equilibrium constants of the following are:${\text{N}}_2+3{\text{H}}_2\rightleftharpoons 2{\text{NH}}_3$ ($K_1$)${\text{N}}_2+{\text{O}}_2\rightleftharpoons 2\text{NO}$ ($K_2$)${\text{H}}_2+\frac{1}{2}{\text{O}}_2\to {\text{H}}_2\text{O}$ ($K_3$)The equilibrium constant ($K$) of the reaction: $2{\text{NH}}_3+\frac{5}{2}{\text{O}}_2\rightleftharpoons 2\text{NO}+3{\text{H}}_2\text{O}$ will be: