某校九年级进行了模拟考试后，张老师对九（2）班全体同学“满分值为6分得一道解答题的得分”情况进行了统计，绘制成下表（学生得分均为整数分）：

由于在填表时不慎把墨水滴在表格上，致使表中数据不完整，但已知全班同学此题的平均得分为4分，结合上表回答下列问题：

（1）九（2）班学生共有多少人？

（2）若本年级学生共有540人，请你用此样本估计整个年级有多少同学此题得满分？

X、Y、Z、M代表四种金属元素。金属X和Z用导线连接放入稀硫酸中时，X溶解，Z极上有氢气放出；若电解Y²⁺和Z²⁺共存的溶液时，Y先析出；把金属X分别浸入M²⁺和Y²⁺的盐溶液中，只有金属Y析出。则这四种金属的活动性由强到弱的顺序为                   

下列各项中，加线词语的意义、用法相同的一项是（  ）

B____ it or not, some plants can eat insects.

阅读下面材料, 在空白处填入适当内容 (一个单词）或括号内单词的适当形式。讲答案填写在答题纸的相应位置。
       What's the most important thing for you to have in your life? Somebody ____ (mention)hard-work, others suggest knowledge, love and luck.
       If you arrange the 26 English letters alphabetically(按字母表的顺序)and use ____(number)to represent each of them, for example, 1 for a, 2 for b, 3 for c…, you can change an English word into a number. So hard-work becomes 8+1+18+4+23+15+18+11=98, meaning 98 is its mark; knowledge: 11+14+15+23+12+5+4+7+5=96, while love :12+15+22+5=54, and luck : 12+21+3+11=47, a small mark. None of these words can give one a full mark. What about money or prayer(祈祷)? They can't , ____.
       Then what else? Don't be worried. You can always find an answer ____a problem in your life, ____you change your way of looking at things or doing things, or your attitude. Yes, attitude is the word. See for____(you): attitude:1+20+20+9+20+21+4+5=100, a full mark.
       Different attitudes lead to different courses of life. Most times people hope for a better life. It is possible ____one will have a change for the better after one has ____(change)one's attitude.
       When you change your manner and became friendly towards others, you'll meet ____ (much)smiling faces towards you. In the same way, if you take a positive attitude towards failure, you'll find it's also rewarding ____it has caused you losses.