U, B, I, P, W,?

More Questions from Series Completion

• AI, BJ, CK,?
• _ stt _ tt _ tts _
• gfe _ ig _ eii _ fei _ gf_ ii
• _ a _ b _ abaa _ bab _ abb
• abca _ bcaab _ ca _ bbc _ a
• _ tu _ rt _ s _ _ usrtu _
• _ _aba _ _ ba _ ab
• c _ bbb _ _ abbbb _ abbb _
• _ bbca _ bcca _ ac _ a _ cb
• a _ bbc _ aab _ cca _ bbcc

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