Chemical Equilibrium question bank (Chemistry)

Solid carbon, CaO and CaCO$_3$ are mixed and allowed to attain equilibrium at T K.
$\text{CaCO}_3(s) \rightleftharpoons \text{CaO}(s) + \text{CO}_2(g) \quad K_{p_1} = 0.08$ atm
$\text{C}(s) + \text{CO}_2(g) \rightleftharpoons 2\text{CO}(g) \quad K_{p_2} = 2$ atm
The partial pressure of CO is ________ $\times 10^{-1}$ atm

Consider the following reactions in which all the reactants and products are present in gaseous state
$2xy \rightleftharpoons x_2 + y_2 \quad K_1 = 2.5\times 10^5$
$xy + \dfrac{1}{2}z_2 \rightleftharpoons xyz \quad K_2 = 5\times 10^{-3}$
The value of $K_3$ for the equilibrium $\dfrac{1}{2}x_2 + \dfrac{1}{2}y_2 + \dfrac{1}{2}z_2 \rightleftharpoons xyz$ is: