Which of the following cannot react as a nucleophile? BH3 H2C=CH2 H2C=NH CH3CH2SH Which of the following can react as a nucleophile? (CH3)3B (CH3)3N (CH3)3CH (CH3)30+ Which of the following reacts most readily as an electrophile? (CH3)4N+ HBr CH3OH CH3Br Which of the following can react readily either as a nucleophile or as an electrophile? (CH3)3B CH3CO2H ○ (CH3)20 H2C=CH2