某学校为了推动球类运动的普及，成立多个球类运动社团，为此，学生会采取抽样调查的方法，从足球、乒乓球、篮球、排球四个项目调查了若干名学生的兴趣爱好（要求每位同学只能选择其中一种自己喜欢的球类运动），并将调查结果绘制成了如下条形统计图和扇形统计图（不完整）．请你根据图中提供的信息，解答下列问题：

（1）本次抽样调查，共调查了多少名学生？

（2）请将条形统计图和扇形统计图补充完整；

（3）若该学校共有学生1800人，根据以上数据分析，试估计选择排球运动的同学约有多少人？

根据短文内容，请将单词填写在题号对应的横线上。

    When we plant a rose seed in the earth,we notice it is small,but we do not criticize it as "rootlees and stemless".We treat it as a seed, ____ （give）it the water and nourishment required ____ a seed.

    When it first ____ （shoot up）out of the earth, we don't condemn（指责）it as ____ （mature） and underdeveloped, ____ do we criticize the buds for not being open when they appear. We stand in wonder at the process ____ （take） place, and give the plant the care it needs at each stage of its development.

    The rose is a rose from the time it is a seed to the time it dies.Within it,at all times,it contains its whole potential. It seems to be ____ （constant） in the process of change: Yet at each state， at each moment, it is perfectly all right as ____ it is.

    A flower is not ____ （good）when it blooms than when it is merely a bud; at each stage it is ____ same thing---a flower in the process of expressing its potential.

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