题目

— How old is her sister?— _______. A . She looks nice B . She is ten years old C . She is in the room D . She is fine 答案：B在一只盛有硫酸铜稀溶液的烧杯中，漂浮着一块木块（如图）．往烧杯中加入少量的某种固体物质后，木块浸没在水中的体积变大（假设在此过程中溶液的体积变化忽略不计）．加入的固体物质可能是（不同类的物质）：（1）______________________________；（2）______________________________；（3）______________________________．