煤气中氧含量高对变换系统有什么危害？

甲国是1982年《联合国海洋法公约》的缔约国。甲国的船舶在各国管辖以外的某海底进行矿产开采作业时，其活动应遵守国际法的哪一种制度?()

A.公海海底的开发制度

B.甲国有关海洋采矿的国内法

C.国际海底区域的开发制度

D.公海自由制度

Healthy knees aren't the main consideration in choosing high heels, but new research says chunky heels are just __________as spindly stilettos (细高跟鞋).  

"It takes a long time to feel the effects of knee osteoarthritis (骨关节炎) — and once you do, it is too ]ate," said Dr. Casey Kerrigan, leading researcher of the study and associate professor at Harvard Medical School's department of physical medicine.

"I compare it to smoking — one cigarette is not painful, but over a lifetime it is. Wide-heeled shoes feel comfortable, so women wear them all day long, "Kerrigan said. "They are better for your feet than stiletto heels, but just as had for your knees."

The idea that high heels are bad for your health isn't new — scientists have warned women for years that they contribute to problems ranging from corns to hammer toes, tendonitis, knee pain, sprained (扭伤) ankles and back problems. 

But in 1998,Kerdgan and a team of Harvard researchers were the first to link high heels and knee osteoarthritis, a painful joint disease that destroys cartilage (软骨) surrounding the knee.

The first study looked only at stiletto heels, and Kerrigan said she wanted to study the chunky high-heeled shoes she noticed many women wearing.

"This study confirms what we all intuitively (直觉地) know that high-heeled shoes of any kind are not good for our health," said Dr. Glenn Pfeifer, a San Francisco doctor and member of the American Academy of Orthopaedic Surgeons who was not connected to the study.

1.What’s the main idea of the passage?

2.Which sentence in the passage is the closest in meaning to the following one?

In my opinion ,it is similar to smoking ,for smoking one cigarette does little harm but if you smoke all your life,it’ll be very painful. 

3.Please fill in the blank in the passage with proper words or phrases to complete the sentence.(within ten words)

4.What do you think of wearing the chunky heels according to the passage?(within 30 words)

5.Translate the underlined sentence into Chinese. 

持续性房颤治疗目的是（）

A.减慢心室率

B.预防心房重构

C.预防血栓栓塞

D.预防房颤复发

E.转复为窦性心律

风热感冒，风寒感冒均可以选用（）

A.荆芥

B.生姜

C.防风

D.桂枝

E.薄荷

2013年11月23日，中国政府发表声明，宣布划设东海防空识别区，并发布航空器识别规则公告和识别区示意图。这一举措（）

①有利于捍卫国家主权和领土领空安全②进一步扩大了我国的领空范围

③表明维护国家主权是我国外交政策的宗旨④是我国有效行使自卫权的必要措施

A.①②

B.①③

C.②③

D.①④