题干

下列客现事实对应的微观解释正确的是(   )

A:把液化气压缩进钢瓶——分子体积变小

B:公园里闻到花的香味——分子不断运动

C:电解水得到象气和氧气——水由氢分子和氧分子构成

D:金刚石和石墨的物理性质差异大——碳原子结构不同

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B

同类题1

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     I was very disappointed not to be able to go to the jazz concert last Friday. The advertisement in the paper said that you could buy tickets at the theatre box in Richland Hills any day between 10:00 and 4:00. Since I work from 9:00 to 5:30, the only time I could go to the theatre was during my 45-minute lunch break.

    Unfortunately, the theatre is on theother side of the town, and the bus service between my office and Richland Hills is not very good. Butif you are lucky, you can make the round trip in 45 minutes. Last Monday, Istood at the bus stop for 15 minutes waiting for the bus, By the time I saw onecome around the corner, there was not enough time left to make the trip.

     So I gave up and went back to the office. The same thing happened on Tuesday, and again next day. On Thursday, my luck changed. I got on a bus right away and arrived at the theatre in exactly 20 minutes. When I got there, however, I found along line of people at the box office, I heard one man say he had been waitingin line for over an hour. Realizing I would not have enough timeto wait in line. I caught the next bus and headed back across the town.

    By Friday I realized my only hope was tomake the trip by taxi, it was expensive, but I felt it would be worth it tohear the concert. The trip by taxi only took 10 minutes, but felt like an hour to me. When I got to the theatre, I was relieved to see that nobody was waiting in line. The reason, however, I quickly discovered, was that they had already sold all the tickets.

同类题3

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    The uninvolved dad, turning up his nose at diapering(换尿布) and too busy to bathe, dress and play with his kids, is mostly a myth(神话) , a big government survey suggests. Most American fathers say they are heavily involved in hands-on parenting, the researchers found.

    The results are encouraging and important " because others have found the more involved dads  are, the better the outcomes for their children. " said researcher Jo Jones of the National Center for Health Statistics, part of the Centers for Disease Control Prevention. She co-authored the report released Friday.

    "Times have changed," said Robert Loftus, 34, of Yonkers, NY. He quit a six-figure sales job a year ago to care for his two young children while his wife works full time. "We are trying to rethink our priorities (优先考虑的事) and family seem to be NO.1 priority while in the past maybe people were more focused on career. "

    The study involved nearly 4.000 fathers who were interviewed in person between 2009 and 2013.

◇ Key findings among fathers living with children younger than 5 :

*9 in 10 bathed, diapered, helped them use the toilet or get dressed at least several times weekly .

* Even higher numbers played with them and ate meals with them that often

* Almost 2 0ut of 3 read to them at least several times weekly.

◇Among dads living with kids aged 5-18.

* More than 9 0ut of 10 ate meals with them at least several times weekly and talked with them about what happened during the kids' day that often.

* Almost 2 0ut of 3 helped with homework several times weekly.

* About half took their kids to or from activities that often.

    Dr. David Hill, a Wilmington, N. C. pediatrician (儿科医生) said the survey reflects what he's seen among his patients' fathers. Increasingly, fathers rather than mothers take their kids to the doctor. Some "are anxious about changing a diaper, " he said.

    Census(调查) numbers show that there were almost 190,000 stay-at-home dads nationwide last year versus 93,000 in 2010. Loftus, the New York stay-at-home dad, said, "I feel fortunate to be able to be such a hands-on father.  I'm doing the most significant occupation in the world. "