I₂+I−⇌I₃⁻. This reaction is set up in aqueous medium. We start with 1 mole of I₂ and 0.5 mol of I⁻ in 1 L flask. After equilibrium, the excess of AgNO₃ gave 0.25 moles of yellow ppt. Then the equilibrium constant is:
a. 1.33
b. 2.66
c. 2.00
d. 3.00