将某生铁样品5.82g，放入烧杯中，再加入过量的稀盐酸，反应时间（t）和烧杯及其所盛物质总质量（m）的关系如图所示：

    Mr. Zhang and Mr. Wang work in the same office. They're good friends.Mr. Zhang says to Mr. Wang in the office,“I would like to have a small party in my home on Sunday evening. Would you and your wife like to come?”

    Mr. Wang says,“Thanks a lot. I'd like to. Let me tell my wife about it.”So Mr. Wang goes to the other office and calls his wife. About half an hour later, he comes back and looks very worried.

    “What's up?” asks Mr. Zhang,“Is your wife at home?”

    “No,” says Mr. Wang.“She isn't at home now , but my little daughter is in .My little daughter says her mother goes out to look for her.”