“六一”儿童节前夕，薪黄县教育局准备给留守儿童赠送一批学习用品，先对浠泉镇浠泉小学的留守儿童人数进行抽样统计，发现各班留守儿童人数分别为6名，7名，8名，10名，12名这五种情形，并将统计结果绘制成了如图所示的两份不完整的统计图：

请根据上述统计图，解答下列问题：

（1）该校有多少个班级？并补充条形统计图；

（2）该校平均每班有多少名留守儿童？留守儿童人数的众数是多少？

（3）若该镇所有小学共有60个教学班，请根据样本数据，估计该镇小学生中，共有多少名留守儿童．

$\sqrt{81}$的平方根是____； $\sqrt{5^2-3^2}$ =____．$$

在直线上标出这四个数，并点出来：﹣$\frac{2}{3}$、$\frac{9}{4}$、1$\frac{1}{2}$、2$\frac{5}{6}$．

2015年 3月5日-15日，十二届全国人大三次会议在北京召开“民之疾苦，国之要事。”“立国之道，惟在富民。”政府工作报告中关于民生问题的表述。下列有利于增进民生福祉，促进社会公平正义与和谐进步的对策是（    ）

①坚持我国的基本经济制度与我国的分配制度相适应

②确定劳动、资本、技术和管理等生产要素按贡献参与分配的原则

③以经济建设为中心，大力发展生产力，实现同步富裕

④健全社会保障体系，加大对弱势群体的帮扶

    In many western schools, sports day is a big event. Children take part in competitive (竞争性的)sports and try to break school records and take the first place.

    Sports days, or sports meetings, are usually held in the warmer seasons, either at the beginning or the end of the school year. They are also called field days. Primary school sports days are fun. They usually have activities such as the egg and the spoon race and the sack race. Other events include the skipping race (跳绳) and the three-legged race. In middle and high schools, sports days include many of the common track and field events (田径项目).  They are more serious and competitive than primary school ones.

    Students' parents and other relatives also come to the school on sports days. They watch children play. Many schools in the West have "mothers and fathers" races for parents to take part in!

    Although sports days are exciting, they also have some problems. According to some reports in the USA, sports days have become too competitive to be good for students. Some parents put too much pressure on the children. Some schools don't have "mothers and fathers" races any more as there is much fighting and cheating.

根据短文内容回答下列问题。