For which of the following reactions is $K_c \leq K_p$ at $298 \ K$?

For the reactions $N_{2(g)} + O_{2(g)} \rightleftharpoons 2NO_{(g)}$ and $NO_{(g)} \rightleftharpoons 1/2N_{2(g)} + 1/2O_{2(g)}$,the equilibrium constants are $K_1$ and $K_2$ respectively. What is the relationship between $K_1$ and $K_2$?

At $1127 \, K$ and $1 \, atm$ pressure,a gaseous mixture of $CO$ and $CO_2$ in equilibrium with solid carbon has $90.55 \%$ $CO$ by mass.
$C_{(s)} + CO_{2(g)} \longleftrightarrow 2CO_{(g)}$
Calculate $K_c$ for this reaction at the above temperature.

For the reaction $SnO_{2(s)} + 2H_{2(g)} \rightleftharpoons 2H_2O_{(g)} + Sn_{(l)}$,at equilibrium,the mixture of steam and hydrogen contains $40\%$ $H_2$ by volume. Find $K_p$ for the reaction.

In which one of the following equilibria,$K_p \neq K_c$?

The equilibrium constant at $850 \ K$ for the reaction $N_{2(g)} + O_{2(g)} \rightleftharpoons 2 NO_{(g)}$ is $0.5625$. The equilibrium concentration of $NO_{(g)}$ is $3.0 \times 10^{-3} \ M$. If the equilibrium concentrations of $N_{2(g)}$ and $O_{2(g)}$ are equal,the concentration of $N_{2(g)}$ in $M$ is