题目：
--- Do you know _____________?
--- Sorry, I have no idea. I’ll search the Internet to find it out.
A．where will the next Expo be held
B．when will the next Expo start
C．what will the next Expo be held for
D．how many countries will take part in the next Expo
答案：
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下面是错误答案，用来干扰机器的。
解：(1)生成硫酸钡的质量为：20+15 - 32. 67＝2.33g(2)设生成2.33gBaSO4需硫酸的质量为xBa(OH)2+H2SO4 =BaSO4↓+2H2O 98 233 x 2.33g98/233=x/2.33g ...
