实验探究。

下列有关细胞全能性和细胞凋亡、细胞坏死的说法正确的是（　　）

如图，位于竖直水平面内的光滑轨道由四分之一圆弧ab和抛物线bc组成，圆弧半径Oa水平，b点为抛物线顶点。已知h=2m,，s=$s=\sqrt{2}m$。取重力加速度大小$g=10m/s^2$。

根据汉语提示写出单词或补全句子。

①____ (也许) we should buy some more beef.

②The Spring Festival is one of the ____ (传统的) Chinese festivals.

③Listen! The music shop is playing a ____ (唱片) of Mozart.

④There is a gym in the____ (中心)of the school.

⑤Do you like taking a____ (慢的)train to travel in the country?

⑥除了音乐，她还喜欢旅游。　____music, she likes travelling as well.

⑦李雷出生于中国的首都北京。　LiLei ____ Beijing, the capital of China.

⑧冼星海以歌曲《黄河大合唱》而闻名。Xian Xinghai ____ the song The Yellow River.

⑨请带你的朋友到花园四处转转。Please____ the garden.

⑩在5岁时，他和父母搬到了广州。　____，he moved to Guangzhou with his parents.

计算（先化简，再求值）： $(\frac{3a-1}{a^2-1}-\frac{2}{a+1})÷\frac{1}{a^2-2a+1}$ ，其中a= $\sqrt{2}+1$ ．