将金属钠分别投入下列物质的水溶液中，既有气体生成又有蓝色沉淀生成的是
A．HCl
B．K2SO4
C．CuCl2
D．Ca(HCO3)2
答案：C
Although he is well off, he is living in a house _____ only 20 square metres. [ ]
A. to measure
B. measured
C. measuring
D. to be measured
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