Classify the reagents shown in bonds in the following equations as nucleophilies or electrophiles. Use curved-arrow notation to show the electron movement.
(a) `CH_3COOH + HO^(Ө) rarr CH_3COO^(Ө) + H_2 O`
(b) `CH_3COCH_3 + NC^(Ө) rarr CH_3C(CN) OHCH_3`
( c) `C_6H_6 + CH_3 overset (oplus) CO rarr C_6H_5COCH_3`.