市盈率估值法属于（）。A．绝对估值法 B．相对估值法 C．主观估值法 D．客观估值法

下列对固体废物的描述不正确的是( )。

A．固体废物是生产、建设、日常生活和其他活动中产生的固态、半固态废弃物质

B．固体废物是一个极其复杂的废物体系，按照其化学组成可分为有机废物和无机废物

C．固态废物必须采用掩埋的方式处理

D．按照其对环境和人类健康的危害程度可以分为一般废物和危险废物

1774年，瑞典化学家舍勒在研究软锰矿（主要成分是MnO₂）的过程中，将它与浓盐酸混合加热，产生了一种黄绿色的气体，有强烈的刺鼻气味．1810年，英国化学家戴维确定这种气体为氯气（Cl₂）．氯气有剧毒，密度比空气大，约为空气密度的2.5倍，能溶于水，氯气的化学性质活泼，能与水、金属、碱等发生化学反应，氯气与氢氧化钠溶液反应生成氯化钠和次氯酸钠（NaClO）．

（1）舍勒发现氯气的方法至今还是实验室制取氯气的主要方法之一．请补充完善其反应的化学方程式：MnO₂+4HCl（浓）

△   .

2H₂O+______+Cl₂↑．

（2）小明用上述反应制取氯气，设计了右图所示装置，请指出其中的问题，并提出改进的方法______．

（3）如果需要获得干燥的氯气，可选用的干燥剂是______（填写序号）．

A．碱石灰       B．浓硫酸        C．氢氧化钠

（4）如右图所示，将干燥的氯气依次通过盛有干燥红纸条的集气瓶A和盛有湿润红纸条的集气瓶B．发现瓶A中的红纸没有变化，而瓶B中的红纸退色了．据此，你能获得什么结论？

你能推断使红纸退色的物质可能是______；理由是______．

消化性溃疡死亡的主要原因（）。

A.十二指肠球部溃疡周边黏膜充血水肿所致

B.十二指肠球部溃疡反复发作瘢痕形成或粘连所致

C.急性穿孔

D.慢性穿孔

E.癌变

My dream ended when I was born. Although I never knew it then, I just held on to something that would never come to pass. Dreams really do exist. But in the morning when you wake up, they are remembered just as a dream. That is what happened to me.

I always had the dream to dance like a beautiful ballerina（芭蕾舞女演员）turning around and around and hearing people applaud for me. When I was young, I would turn around and around in the fields of wildflowers that grew in my backyard. 

Reality woke me up when I heard someone saying, "I don't know why you bother trying to dance. Ballerinas are pretty and slender(苗条) girls. Besides, you don't have the talent to even be a ballerina." I remember how those words hurt every feeling in my body. I fell to the ground and wept for hours. 

I enjoyed hanging out by the water. I would sit there for hours and stare at my reflection(倒影). There I was, looking nothing like a pretty ballerina dancer. Reflections don't lie. Once the waves would come, my reflection was washed away just like my dream to dance.

As I grew older, I began to realize that the reason my dream was even born was because it was something that was inside of me. The dream I had was never nurtured(培育) and cared for, so it slowly died. It's not that I wanted it to die, but I allowed it to die the day I started listening to the words, "You can't do it." When I finally woke up from many years of dreaming, I realized that you can't only settle for dancing in the wildflowers, you have to move on to the platform.

小题1: Which of the following can serve as the best title for the passage？

A．Care for your dream

B．Dream and reality

C．Nothing is impossible

D．Efforts to be a ballerina will pay 小题2:The author didn’t realize her dream of being a ballerina mainly because_______.

A．she was bored of dancing and performing

B．she had lack of self-respect

C．her health conditions allowed her dream to die

D．she was deeply affected by others easily小题3:From the passage, it can be inferred that _________.

A．the author was once a pretty and slender girl with wonderful dream.

B．we should dare to give up our dream facing much pressure and difficulty

C．if you stick to your dream and never say die, you will enjoy a bright life

D．You should necer give up.小题4:What is the main purpose of writing the passage?

A．to complain

B．to praise

C．to warn

D．to criticize小题5:The underlined expression “settle for” in the last paragraph means_________.

A．turn down

B．take up

C．give up

D．settle down

某同学用30%的蔗糖溶液来处理某生物细胞，在操作步骤完全正确的情况下，细胞没有出现质壁分离现象。试分析该同学所使用的实验材料可能是（）①根尖分生区细胞②动物细胞③死细胞④去除了细胞壁的植物细胞

A.②④

B.①②④

C.②③④

D.①②③④