题干

在“探究水沸腾时温度变化的特点”实验中,小明和小华所用器材的规格完全相同、杯中水的质量相同、且水在单位时间内吸收的热量也相同(忽略水在沸腾前质量的变化).

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同类题4

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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5

阅读理解

    Norman Borlaug, who is making a difference, is known around the world. He is often described as the man who has saved more lives than any other person in history. Norman Borlaug is considered the father of what has been called the Green Revolution. His ideas about agriculture increased crop production and ended hunger in many nations. Mr. Borlaug continues to be a leader among agricultural researchers.

    Norman Borlaug was born in 1914 on a farm in the American state of Iowa. In the middle of the 20th century, world population was expanding faster than food production. Experts said many people in developing countries would face starvation.

    Norman Borlaug was an agricultural researcher at the International Maize and Wheat Improvement Center in Mexico. He developed methods of growing wheat that increased the amount harvested by three times. He later repeated this success in India, Pakistan and Africa.

    His methods of farming saved millions of people who would have starved to death. Norman Borlaug was given the Nobel Peace Prize for his efforts in 1970.

    Norman Borlaug is still urging experts to think about the needs of people around the world. His latest concern is a disease in wheat called UG99. He says it has the power to destroy most of the wheat being grown around the world. He says reductions in agricultural programs have made it harder to take action against such threats.

    Mr. Borlaug's granddaughter Julie works at the center named after him at Texas A&M University in Dallas. She says his worry about food problems rises from the belief that hunger is unacceptable. She says Norman Borlaug still believes it is our responsibility as human beings to feed one another.