Total number of isomers (structural and stereo) possible with the formula, C2H4O2 is ‘A’. Number of structurally isomeric esters possible with the formula, C2H4O2 is ‘B’. Sum of A and B is

Total number of isomers = 3 ;Total number of structural isomers = 3 ;Total number of isomeric carboxylic acids (structural and stereo) = 1 ;Total number of structurally isomeric carboxylic acids = 1 ;Total number of isomeric hydroxy carbonyl compounds (structural and stereo) = 1 ;Total number of structurally isomeric hydroxy carbonyl compounds = 1 ;Total number of isomeric hydroxy aldehydes (structural and stereo) = 1 ;Total number of structurally isomeric hydroxy aldehydes = 1 ;Total number of isomeric esters (structural and stereo) = 1 ;Total number of structurally isomeric esters  = 1 ;