多项式y²-2my+1是一个完全平方式，则m的值是(     )

轮船总是漂浮在水面上，一艘轮船从河里驶向大海，它受到的重力大小　____ 　（变大、变小、不变）；它受到的浮力大小　____ 　（变大、变小、不变）；它排开水的体积____ （变大、变小、不变）；轮船是下沉些还是上浮些　____ 　．

——__________Internet business          traditional business in the past few years? ——Not really.

阅读理解A

    Hello,everybody!Look at this picture．This is a nice Sunday afternoon．My family are having a great time．
    I am Bob．I am having bread and listening to my father telling me a story from the newspaper．He thinks it's interesting．Look at my mom．She is listening to the radio．She likes music on it．My two sisters Rose and Sally are plying．Rose is only one year old and Sally is three.My grandpa is having a nap(打盹)．He always has a nap when he has nothing to do．My grandma is drinking a cup of tea．She likes her tea with a lot of milk in it．My cousins are busy．Ken is watering the flowers(浇花)and Mike is cleaning the windows(窗户)．Where is my pet cat Pussy? Oh, it is running after the birds．
    I really like an afternoon like this．
根据材料内容选择最佳答案。

“华罗庚”杯数学竞赛获奖的87名学生分别来自12所小学。试说明至少有8名学生来自同一所学校。