近期《美国化学会志》报道,中国科学家以二氧化碳为碳源,金属钠为还原剂,在470℃

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问题:

近期《美国化学会志》报道,中国科学家以二氧化碳为碳源,金属钠为还原剂,在470℃、80Mpa下合成出金刚石,具有深远意义。下列说法不正确的是 [ ]

A.由二氧化碳合成金刚石是化学变化

B.金刚石是碳的一种同位素

C.钠被氧化最终生成碳酸钠

D.金刚石中只含有非极性共价键

考点:氧化产物、还原产物同位素极性键、非极性键
题型:选择题
阅读理解。
                                               FOUND
Black wallet with some money.
Come to Room 502 in the evening, or call 9796788.

                                        WANTED IMMEDIATELY
A boy or a girl to deliver newspapers
Hours: 3:30 a.m. to 8:30 a.m. Mon. to Sat.
Pay:  $ 10 per day
Call:  Mr. Jones at 8947659

                                        SUMMER JOB
     Do you like to talk with people? Do you like to write stories? Do you want to work
for a magazine? Then come and work for us as a reporter.
Please call Karen at 5558823.

                                   HIKING CLUB
Join us for a 10-mile country walk
On Saturday, October 5th
Children and Market Square at 2 p.m.
Call Jeff on 3338651 for more information.

                              SINGLES' CLUB 
 A club for single (单身) people looking for new friends.
Ages: 25-40
Activities: parties, swimming, concerts, dances...
We meet every Friday at 8:30 p.m. 28 Garden Street
Tel: 7026449
E-mail: singleclub@yahoo. com
1. If you have lost a black wallet, you can call ______ to ask for it.
A. 3338651
B. 8947659
C. 7026449
D. 9796788
2. Mr Green wants to go hiking with his children. They should meet at the Market Square _______.
A. at 8:00 a.m. on Saturday morning
B. at 2 p.m. on October 5th
C. at 6:30 a.m. on Monday
D. on Sunday morning
3. Who can join the Singles' Club?
A. A 23-year-old young man.
B. A 28-year-old single man.
C. A 50-year-old single lady.
D. A 28-year-old married (已婚) woman.
4. Alice wants to practice writing stories in her summer holiday. She may ______ for more information.
A. send at e-mail to singleclub@yahoo.com
B. join the Hiking Club
C. call Karen
D. call Mr. Jones
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从夏朝历史分析,国家有哪些暴力机构?当时国家 * * 的象征是什么?

_____________________________________________________

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不具有主体资格的经营机构因从事期货经纪业务,未按客户的交易指令入市交易,客户没有过错的,该机构应当赔偿客户的损失。赔偿损失的范围包括()。

A.推断盈利、税金及利息

B.交易手续费、税金及本金

C.推断盈利、交易手续费及利息

D.交易手续费、税金及利息

题型:选择题

( )属于企业的留存收益。

A.盈余公积和未分配利润

B.资本公积和实收资本

C.盈余公积和实收资本

D.资本公积和末分配利润

题型:选择题

某实验小组在测某种液体密度时,只测了四组液体的体积及容器和液体的总质量,记录数据如下表.请根据记录数据解答有关问题.

(1)求被测液体的密度;

(2)求实验所用容器的质量;

(3)如图所示是该实验小组所画的总质量m随液体体积V变化的图像,其坐标原点为O(0,0),说明图线延长线与纵轴交点P的物理意义.

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