А)C2H5COOH +Na2S-->
Б)CH3COOH+Li-->
В)C2H5OH+CH3OH-->

2СH3-CH2-COOH + Na2S -> 2CH3-CH2-COONa + H2S↓ 2CH3COOH + 2Li -> 2CH3COOLi + H2↑ CH3-CH2-OH + HO-CH3 -> CH3-CH2-O-CH3 + H2O