Dissociation Questions

A weak acid, $\text{HA}$, has a $K_a$ of $1.00\times 10^{-5}$. If $0.100\text{ mole}$ of this acid is dissolved in one litre of water, the percentage of acid dissociated at equilibrium is closest to:

For the reactions $X\rightleftharpoons 2Y$ and $A\rightleftharpoons 2B$, the equilibrium constants are $K_{p1}$ and $K_{p2}$ in the ratio $9:1$. If degree of dissociation is equal, the ratio of total pressures is: