A:CuSO4溶液与Ba (OH)2溶液反应:Ba2++SO42﹣═BaSO4↓
B:NaHSO4溶液和NaHCO3溶液反应:H++HCO3﹣═H2O+CO2↑
C:氯化铝溶液中加入过量氨水:Al3++4NH3•H2O═AlO2﹣+4NH4++2H2O
D:往BaCl2溶液中通入少量的SO2:Ba2++SO2+H2O═BaSO3↓+2H+
Daming lives in the____ ____with his mother.
如图,在周长为20cm的▱ABCD中,AB≠AD,对角线AC、BD相交于点O,OE⊥BD交AD于E,则△ABE的周长为( )