凡进行有危险性的实验，应先检查防护措施，确证防护妥当后，才可进行实验。

世界煤炭储量在世界能源总储量中占90%，按目前规模开采可持续200年左右。据19世纪80年代初世界能源会议等组织的资料，世界煤炭资源地质储量为14.3万亿吨，其中探明储量为3.5万亿吨，约占24.5%；在总储量中硬煤占75%，褐煤占25%。硬煤可采储量以美国、俄罗斯、中国最为丰富，分别占世界总量的24.8%、21.5%、19.6%，共占。

全球已探明的煤炭储量约占世界能源总储量的（）。

A．19%

B．20%

C．22%

D．24%

建设工程要避免不断提高质量目标的倾向，这是建设工程质量控制的( )应考虑的。

A．系统控制

B．全过程控制

C．全方位控制

D．投资控制

以下哪种是多感官教学方法？（）

A.触摸数字方法

B.字头概括法

C.图示组织策略

D.笔记引导策略

下面是学习了化学第二单元课题3后，进行“高锰酸钾制取氧气和氧气性质”的探究，请你回忆并回答下列探究内容：

制取并收集两瓶氧气时，我用高锰酸钾制取氧气，试管口需放一团______；收集纯净的氧气宜选择的收集方法是______．化学反应的文字表达式为______．

Home to me means a sense of familiarity and nostalgia(怀旧). It's fun to come home. It looks the same. It smells the same. You'll realize what's changed is you. Home is where we can remember pain, live, and some other experiences; We parted here; My parents met here; I won three championships here.

If I close my eyes, I can still have a clear picture in mind of my first home. I walk in the door and see a brown sofa surrounding a low glass-top wooden table. To the right of the living room is my first bedroom. It's empty, but it's where my earliest memories are.

There is the dining room table where I celebrated birthdays, and where I cried on Halloween-when I didn't want to wear the skirt my mother made for me. I always liked standing on that table because it made me feel tall and strong. If I sit at this table, I can see my favorite room in the house, my parents' room. It is simple: a brown wooden dresser lines the right side of the wall next to a television and a couple of photos of my grandparents on each side. Their bed is my safe zone. I can jump on it anytime - waking up my parents if I am scared or if I have an important announcement that cannot wait until the morning.

I'm lucky because I know my first home still exists. It exists in my mind and heart, on a physical property (住宅) on West 64th street on the western edge of Los Angeles. It is proof I lived, I grew and I learned.

Sometimes when I feel lost, I lie down and shut my eyes, and I go home. I know it's where I'll find my family, my dogs, and my belongings. I purposely leave the window open at night because I know I'll be blamed by Mom. But I don't mind, because I want to hear her say my name, which reminds me I'm home.

小题1:Why does the author call her parents' bed her "safe zone"(Paragraph 3)?

A．It is her favorite place to play.

B．Her needs can be satisfied there.

C．Her grandparents' photos are lined on each side.

D．Her parents always play together with her there.小题2:What can be learned from the passage?

A．The old furniture is still in the author's fist bedroom.

B．The author can still visit her first physical home in Los Angeles.

C．The author's favorite room in her first home is the dining room.

D．Many people of the author's age can still find their first physical homes.小题3:Sometimes when she feels lost, the author will _______.

A．Open the window at night

B．lie down in bed to have a dream

C．try to bring back a sense of home

D．go to Los Angeles to visit her mom小题4:What is the author's purpose of writing this passage?

A．To express how much she is attached to her home.

B．To declare how much she loves her first house.

C．To describe the state of her family.

D．To look back on her childhood.