已知函数f(x)的定义域为$1,+\infty )$，且f(2)=f(4)=1,$f^{\text{'}}\left(x\right)$为$f\left(x\right)$的导函数，函数$y=f^{\text{'}}\left(x\right)$的图象如图所示.则不等式组$\left\{\begin{array}{c}\begin{array}{c}x\ge 0\\ y\ge 0\\ f\left(2x+y\right)\le 1\end{array}\\ \end{array}\right.$所表示的平面区域的面积是(     )

如图，在2×2正方形网格中，以格点为顶点的△ABC的面积等于$\frac{3}{2}$，则sin∠CAB=（　　）

将一些半径相同的小圆片按下图所示的规律摆放：第1个图形有6个小圆片，第2个图形有10个小圆片，第3个图形有16个小圆片，第4个图形有24个小圆片，……依此规律，第11个图形中小圆片的个数为（    ）.

增加： 在缺词处加一个漏字符号（/\）, 并在其下面写出该加的词。

删除： 把多余的词用（\）划掉。

修改： 在错的词下划一横线, 并在该词下面写出修改的词。

注意：1. 每处错误及其修改均仅限一词；2. 只允许修改10处, 多者（从第11处起）不计分。

    Dear the teachers and schoolmates, it's a great honor for me to be here today and share my experiences of learning English with you. I want to learn English good to take good job, so I learn English in some difference ways. In class, I learn new words, useful expressions and grammar and take efforts to understand the texts under the help of our English teacher. After class, you do a lot of exercises prepare for the college entrance examination. I also read news and watch videos on the Internet and from other source. I have a lot of fun especial when learning English with cartoon movies.

      作文
      请以“乐在其中”为题目，写一篇不少于600字的文章，文体不限。