题干

如图所示的机械中,不计摩擦和绳重,属于同一类杠杆的是(   )

①镊子               ②天平             ③定滑轮      ④开瓶器

A:①④

B:②③

C:①③

D:②④

上一题 下一题 0.0难度 选择题 更新时间:2019-07-12 03:02:20

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B

同类题1

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    Christmas is a time for relaxing, having fun and spending time with family and friends.____It can be difficult to find the motivation for study when everyone around you is having so much fun. So, here are my top five tips for revising effectively over the Christmas break.

    Set aside a few hours a day to revise.

    Find the best time to revise and make sure that you stick to your timetable! For example, I find that I work best in the morning.____

Plan something fun to do every day.

    Even if it's just going for coffee with a friend or watching a film at home, this will give you something to look forward to and motivate you to finish your revision.

    Explain to your family why your revision is important.

    ____So, make efforts to tell them why your exams are important. Perhaps you can agree to do something nice with them when your exams are over.

    ____

    It is important to take some time to relax. When you do get back to revising, you'll probably find it easier to concentrate. Pick the most important days for you and your family to concentrate on celebrating Christmas!

    Remember that it won't last forever.

    You might have to spend your Christmas revising this year, and perhaps for a few more years, but soon enough you'll be free of exams forever.____Have a great Christmas and make sure you find a balance between studying and celebrating. Good luck in your exams!

A. Spare your time for your family.

B. Make sure that you take a few days off!

C. So I get up fairly early and do a few hours of revision.

D. Sometimes it can be difficult for family to understand you.

E. However, for many of us, it is also time to prepare for January exams.

F. Otherwise, you may probably fall into trouble with your friends and family.

G. And after spending time revising, your future Christmases will seem even better!

同类题2

【历史-选修:历史上重大改革回眸】

材料一:(路德说)“我呼吁每一个人应该善待犹太人,同时教他们研读《圣经》这样做,我想我们可以争取他们到我们这边来。”但当路德发现犹太人并不相应地转向新教时,他失望了,他曾经说:“我不允许任何人批判我的主张,即便是天使,凡不接受我的主张者就不能得救。”他开始仅仅反对放高利贷的犹太人,后来发展到反对一般的犹太人。1735年,当选帝侯约翰在萨克森驱逐犹太人时,一个犹太人曾经请路德出面调停,但他竟一口拒绝。他在《桌边细谈》一书中把“犹太人与教皇信奉者”视为“一丘之貉”的不敬神的坏蛋。晚年的路德要是公开指责犹太人,说他们是“一个僵颈、不信神、骄傲、邪恶、可厌的民族”,并声称:他们的学校及教堂应被付之一炬。

——威尔·杜兰《世界文明史》

材料二:马丁·路德所领导的德国宗教改革在客观上有反封建的意义,因为他所反对的天主教会是封建统治的强大的支柱。而且,与僵化了的天主教神学不同,路德的新教容许个人在教义解释上有更大的自由,因而蕴藏着自由主义及个人主义因素,带有资产阶级倾向。但是,路德的新教仍未完全摆脱中世纪经院思想的影响。他反对叛乱,他说:“叛乱不是正当的,不管它如何合乎正义;它的结果从来都是损害大干利益。……因为叛乱发生后必然造成损失和流血。”

——吴于廑、齐世荣《世界史》