(A)H(COO)2ca+(H3CCOO)2caΔ→2CH3CHO+H2(B)CH3CH(OH)CH3cu/300∘C→CH3COCH3+h2(C)CH3CH2OHAg/300∘C→Ch3CHO+H2(D)CH2=CH2+PdCl2+H2OCaCl2⟶H⊕CH3CHO+pd+2HCl