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随着轻工业的飞速发展，城市内彩色电视已经普及，电视的开关及换台均用遥控器控制，张兵在家看完电视后，习惯用遥控器关闭电视，但他却发现此时电视机上的指示灯还在亮，（处于待机状态）猜想可能此时还有电能消耗，于是某假期，父母出差时，便将所用电器停止工作，使电视处于待机状态，3天后，他观察到电能表上的计数器由02685变为02692试问：

（1）张兵家电视待机状态时消耗多少千瓦时电能？

（2）若张兵所在城市估计有10万台电视，假设平均每台每天处于待机状态15h，待机功率与张兵家相同．（每月按30天计算）共浪费电能多少千瓦时？

天然气热值为4.6×107J/m3，上述电能均为家庭使用，相当于节约多少m3的天然气？（假定天然气的利用率为80%）

答案

（1）由题意可知消耗的电能W=269.2kw•h-268.5kw•h=0.7kw•h．

答：张兵家电视待机状态时消耗0.7千瓦时电能．

（2）张兵家三天（72h）消耗电能0.7kw•h，

所以电视机在待机状态下消耗的电功率P=

W
t
=
0.7kw•h
72h
=
0.7
72
kw，

每个月张兵所在城市共浪费电能W总=Pt总=

0.7
72
kw×15h×30×100000=4.375×105kw•h=1.575×1012J．

由题中效率可知若用天然气所需总能量W气=

W总
η
=
1.575×1012J
0.8
=1.96875×1012J，

由热值单位的物理意义可知所需天然气

V=

W总
q
=
1.96875×1012J
4.6×107J/m3
≈4.3×104m3．

答：共浪费电能4.375×105kw•h；相当于节约4.3×104m3的天然气．

单项选择题 A1型题

滋养细胞肿瘤的随访指标中，除血尿hCG外，下列哪一项最有价值（）

A.肺X线片

B.妇科检查

C.子宫双附件B超

D.肝脏B超

E.基础体温
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完形填空

My grandfather took me to the fish pond on the farm when I was seven. He told me to throw a__21____into the water. And he told me to watch the____22___created by the stone. Then he asked me to__ 23__ of myself as that stone.

“You may24 lots of splashes (飞溅 ) in your life,___ 25___the waves that come from those splashes will ___26____the peace of all your fellow___27_____,”he said.

“Remember that you are ___28____for what you put in your circle and that the circle will also___29____many other circles. You will need to live in the ___30____that allows the good that comes from your circle to ___31____the peace of that goodness to___32____. The splash that comes from anger or jealousy will send those___33_____to other circles. You are responsible for____34_____.”

That was the first time I ___35_____each person creates the inner peace or discord (冲突) that ____36_____out into the world. We cannot create world peace if we are ___37____with inner conflicts, hatred, ____38______, or anger. We radiate (流露) the feelings and thoughts that we hold ____39_____,whether we speak them out or not. Whatever is splashing around inside of us is spilling out into the world, creating beauty or discord with all other circles of life.

We are ____40_____to everything and everyone else around in the universe.

21. A. stick    B. brick     C. stone      D. ball

22. A. holes    B. circles    C. drops      D. waters

23. A. think    B. accuse    C. regard     D. warn

24. A. produce  B. damage   C. prevent    D. create

25. A. but      B. because   C. while      D. for

26. A. cut      B. disturb    C. bring      D. block

27. A. students  B. friends    C. creatures   D. workers

28. A. proud    B. helpful    C. respectful   D. responsible

29. A. hear     B. leave      C. strike      D. touch

30. A. family   B. situation    C. way       D. hurry

31. A. send     B. provide    C. destroy     D. keep

32. A. them     B. nobody    C. someone    D. others

33. A. tastes     B. smells     C. feelings    D. views

34. A. all       B. both       C. neither     D. any

35. A. realized   B. recognized   C. admitted   D. promised

36. A. flows     B. takes       C. picks       D. brings

37. A. prepared   B. filled      C. presented    D. supplied

38. A. honesty    B. truth       C. doubt      D. modesty

39. A. forward    B. outside     C. inside      D. upward  

40. A. referred    B. intended    C. devoted    D. connected
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