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The Ko values for four bases are: CN- 1.6 x 10-3 2.1 x 104 1.8 x 10-5 F- 1.5 x 10-11 The pH's of 0.50 mol/L solutions of each of these weak bases were measured and the bases were placed in order, from highest pl to lowest pH. The result was which of the following? O CN , CO; , NH,, F- O CO; , NH,, CN-, F- O F-, CN-, NH,, CO- O CO; CN-, NH,, F