A:CH3COOH(aq) + NaOH(aq) ='=' CH3COONa(aq) + H2O(l);△H1
B:NaOH(aq) + 1/2H2SO4(aq) ='=' 1/2Na2SO4(aq) + H2O(l);△H2
C:NaOH(aq) + HCl(aq) ='=' NaCl(aq) + H2O(l);△H3
D:NaOH(aq) + 1/2H2SO4(浓) ='=' 1/2Na2SO4(aq) + H2O(l);△H4
None of my friends ______at 10, so I realized it was a trick and felt really embarrassed.
为什么说治水必躬亲?用课文《治水必躬亲》中句子回答。