17. Acid and Base Equilibrium

What is the pH of a 0.145 M solution of (CH3)3N (trimethylamine), given that Kb for (CH3)3N is 6.4 × 10^{-5}?

A student claims that the pH of a $2.65\times M$ aqueous solution of methylamine, ${\mathrm{CH}}_3{\mathrm{NH}}_2$, is 12.54. Given $K_b=4.4\times {10}^{-4}$ for ${\mathrm{CH}}_3{\mathrm{NH}}_2$ at 25 °C, which pH is most reasonable (assuming $x\ll 2.65$)?