如图所示,一个立方体玻璃砖的边长为a,折射率n=1.5,立方体中心有一个小气泡.

题型:计算题

问题:

如图所示,一个立方体玻璃砖的边长为a,折射率n=1.5,立方体中心有一个小气泡.为使从立方体外面各个方向都看不到小气泡,必须在每个面上都贴一张纸片,则每张纸片的最小面积为多少?

考点:全反射,临界角
题型:计算题

There are quite a few advantages of wearing school uniforms. The idea may seem disagreeable at first, but considering all the positive effective coming from wearing uniforms you would be more likely to enjoy them.

Teachers love school uniforms because it helps provide an orderly learning environment. Having students dressed in uniforms may teach them how to present themselves in a neat(整洁的)and professional manner. It gives students the opportunity to learn how to dress like young ladies and gentleman. And they can focus their attention on academics rather than style.

Purchasing school uniforms is easy and needs less hesitation(犹豫) and consideration. No matter what the school’ s policy is, there are only specific essential(基本的) pieces to the wardrobe(服装) that are necessary, so it won’t break the bank. A few wardrobe items can last a long time. Parents could also enjoy an easy morning, as it will take less time to choose a set of clothes for the school day.

Students wearing uniforms will feel less pressure about what to wear or not to wear when their classmates are dressed similarly. Getting dressed before school becomes less of a chore when students are limited in their choices, so there shouldn’t be any trouble about choosing an outfit for the day and getting ready quickly. Some students may not like the lack of individuality(个性) with a uniform, but some school dress code policies may offer them the opportunities to show their unique styles.

Uniforms today are also becoming trendier and can be seen in many areas of pop culture. Celebrities and fashion designers are using uniforms as inspiration for new looks which also appeal to students.

小题1:What would be the best title for the text?

A.How to dress properly.

B.The history of school uniforms.

C.The advantages of school uniforms.

D.How to deal with pressure in school.小题2:Teachers think that wearing school uniforms ________________.

A.is just a tradition that students should follow

B.makes students feel less pressure in study

C.helps students put more effort into their studies

D.makes students lose their independence and identity小题3:The underlined part “it won’t break the bank” in Paragraph 3 probably means “___________”.

A.a school uniform doesn’t cost a lot of money

B.a school uniform should be worn every day

C.parents will have to go to the bank many times

D.parents who work in a bank can afford the uniform小题4:We can infer from the text that school uniforms _________.

A.are not popular with fashion designers

B.were not accepted by parents in the past

C.will be designed by students themselves

D.will be more fashionable in the future小题5:The author’s attitude towards students’ wearing school uniforms is ___________.

A.negative

B.supportive

C.doubtful

D.unclear

题型:计算题

婴儿口腔清洁法操作哪项是错误的()

A.每次喂奶之后,用清洁纱布裹于手指或用指套牙刷轻柔擦洗口腔组织及牙龈

B.第一颗牙萌出后用儿童牙刷帮助刷牙

C.预防奶瓶龋,喂给不含蔗糖的饮料与流食

D.喂药或其他营养品后应用清洁水帮助洁牙

E.针对某些危险因素保持一定的预防措施

题型:计算题

男性,25岁,反复哮喘发作20年,严重发作已持续48小时。查体:呼吸困难,发绀,烦躁,双肺呼吸音低,可闻及散在哮鸣音,心率124次/分,有奇脉。下列哪项措施是错误的()

A.静脉补充5%葡萄糖盐水

B.静脉给予氨茶碱,但一般应<1.0g/d

C.静脉给予甲基强的松龙40mg,每6h

D.经压缩空气泵雾化吸入β2受体兴奋剂

E.肌注苯巴比妥

题型:计算题

每份检定、校准或检测记录应包含足够的信息,以便于在可能时识别(),并保证该检定、校准或检测在尽可能与原来条件接近的条件下能够复现。

A.不确定度的影响因素

B.测量设备的影响

C.误差的影响量

D.环境的影响因素

题型:计算题

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