题目

在“探究串联电路特点”时小明选用两只规格不相同的灯泡连接的电路如图1所示。 (1)闭合开关S后，发现灯L1发光，L2不发光。同学们有以下几种猜想： ①L2灯丝断了；②L2短路；③灯L2也工作，但L2的电阻比L1的小。以上猜想中正确有______（填序号）； (2)为了寻找“串联电路的电流关系”，分别把图1中A，B，C各点断开，然后把______接入，闭合开关前指针如图2所示，则______；闭合开关后，发现其中一个电表指针如图2所示，出现这种现象的原因是______； 第三部分阅读理解（共20小题；每小题2分，满分40分）阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该项涂黑。Looking back at my school yearbooks of the 1970s, 80s, and 90s, I find the style of uniform says a lot about the students and the character of the times. In the 1970s, students accessorized (配饰) their uniforms with platform shoes. During the 80s, hair was huge—literally. Students’ goofy hair filled up nearly every shot in the yearbook. In the 90s, accessories were all the rage (流行).Uniform rules have always been strict. The restrictions (限制) are down to the inch: Gray or plaid skirts must be no shorter than two inches above the knee; a red, green, navy or white polo must be worn at all times; and only white, blue, black, and gray sneakers or flats are allowed. With all these rules, one can’t help but wonder how the typical rebellious (叛逆的) teenager can express her individuality.Still, they manage. Senior Michelle Ferrier says she accessorizes by wearing bright colors like green and pink in bracelets, shoe laces, and headbands to stand out and be fashionable. For any stylish (时尚的) Carondelet student, accessories are key.At Carondelet, one thing’s for sure: The older a student gets, the more she’s willing to bend the rules. Senior Natalia Piwek admits that she often pairs her “tights and colorful socks” with “illegal shoes”. If you happen to see a girl with colorful tights or boots running across the hallway, it’s most likely that she’s running from a dean.In about two months, I will say goodbye to my uniform. I will miss the convenience of wearing it. However, I must say, wearing a uniform has taught me an important lesson that I will take with me when I go off to college: it doesn’t matter what you wear, but how you wear it. And how you carry yourself.56．In the 1980s, _________. A．uniform rules are sneer B．students preferred goofy hair C．accessories were popular with students D．students wrote colorful shoes with uniforms57．Which of the following combinations might the students think stylish? a. grey bracelets     b. parks shoes laces C. green heathens d. patterned tights   E. red polo A．abe   B．bde   C．bcd   D．ace58．According to the students, the restrictions of uniforms are_______. A．atcler              B．understanding childish C．childish           D．unselfishly59．What’s the author’s attitude towards wearing school uniforms? A．Objictive. B．Tolerant.   C．Agreenble.       D．Oppcaitive.60．What is the main point of the text? A．The history of student’s uniforms. B．How to make school uniforms stylish. C．Memories and lessons From school uniforms. D．The debate oven restrictions on school uniforms.