A:加强植树造林
B:珍惜身边草木
C:随意排放污水
D:维护绿色生态
①____ Na2S2O3+____HCl→____ NaCl+____S+____SO2↑+
____H2O
②____ Zn+____H++____NO3﹣→____ Zn2++____NH4++____H2O.