题干

如图所示电路,电源电压为6V且保持不变,滑动变阻器R1标有“50Ω 2A”字样.

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同类题2

阅读下列材料:

为落实开展社会大课堂活动,七年级(3)班李老师准备周六组织本班学生参观北京科技馆,要求学生周六早9:00准时在科技馆门前集合,然后几种买票参观.

小强家离北京科技馆4公里,周六他准备乘出租车去,为了解北京出租车的计价方式,小强周五晚上在网上查到了现行北京市出租车价格标准:

收费项目

收费标准

3公里以内收费

13元

基本单价

2.3元/公里

低速行驶和等候费

根据乘客要求停车等候或由于道路条件限制,时速低于12公里时,每5分钟早晚高峰期间加收2公里租价(不含空驶费)其他时间段加收1公里租价(不含空驶费)

预约叫车服务费

提前4小时以上预约每次6元,4小时以内预约每次5元

空驶费

单程旅客行驶超过15公里部分,基本单价加收50%的费用,往返载客(即起点和终点在2公里(含)范围以内)不加收空驶费

夜间收费

23:00(含)至次日5:00(不含)运营时,基本单价加收20%的费用

合乘收费

合乘里程部分,按非合乘情况下应付金额的60%付费

燃油附加费

1元/运次

备注:1、早高峰7:00(含)﹣﹣9:00(不含);晚高峰17:00(含)﹣﹣19:00(不含).

      2、出租车计价段里程精确到500米,时间精确到2.5分钟;出租汽车收费结算以元为单位,元以下四舍五入.

      3、过路、过桥费由乘客负担.

      4、按日结算的包车及出北京行政区域的客运业务收费实行市场调节价.

在仔细阅读标准后,小强准备周六早上8点10分乘车,路上留出10分钟出租车时速低于12公里的堵车时间,这样在9点之前一定能顺利到达科技馆.时间设计好后,经过计算小强向妈妈要30元打车钱,妈妈问他30元钱够吗?小强说:“我按上表计算了,30元钱还有几块钱的剩余呢.”

下面是小强的分析与计算过程,请补充完整:

同类题3

阅读理解

    Last April, on a Sunday, we took one of our “nowhere” drives. My husband was quietly driving along a back road. I was occupied in the front passenger seat watching the scenery.

    I noticed out of the corner of my eye that my husband was struggling to look out of my window. This frightened me, since his eyes should be on the road in front of him. I asked him what he was looking at out of the windows, and he quietly replied, “Nothing.”

    After a few minutes, I looked over at my husband and noticed a tear running down his cheek. I asked him what was wrong. This time he told me, “I was just thinking about Pop and a story he had once told me.” It had something to do with Pop, his friend from childhood, and I wanted to know the story, so I asked him to share it with me.

    He said, “When I was 8 years old, Pop and I were out fishing and he told me that the pine trees know when it is Easter.”

    I have no idea what he meant by that, so I pressed him for more information.

    He continued on… “The pine trees start their new growth in the weeks before Easter because spring is drawing near. If you look at the tops of the pine trees, you will see the yellow shoots. As the days get closer to Easter Sunday, the tallest shoot will branch off and form a cross. By the time Easter Sunday comes around, you will see that most of the pine trees will have small yellow crosses on all of the tallest shoots.”

    I turned to look out of the window and I couldn't believe my eyes. It was a week before Easter, and you could see all of the trees with the tall yellow shoots stretching to the sky.

    The tallest ones shone in the sunlight like rows of tiny golden crosses. May you find your Easter season filled with beautiful golden crosses!