有一种环保汽车,以蓄电池为驱动能源.此环保汽车运动时,蓄电池为车上的电动机供电,

题型:问答题

问题:

有一种环保汽车,以蓄电池为驱动能源.此环保汽车运动时,蓄电池为车上的电动机供电,电动机为汽车提供动力.某辆这种类型的环保汽车,总质量为3×103kg,汽车轮胎与地面的总接触面积为0.1m2.当它在水平路面上匀速行驶时,电动机工作电流为50A,工作电压为300V,汽车所受阻力为车重的0.04倍.(g取10N/kg)

(1)汽车对路面的压强多大?

(2)若该汽车用于牵引汽车前进的机械功率和电动机电功率的比值为4:5,则该车匀速前进的速度多大?

考点:压强的大小及其计算功率的计算电功率与电压、电流的关系
题型:问答题

商品房屋租赁登记备案证明上,应载明的内容包括()等。

A.出租人姓名(名称)

B.有效身份证件种类和号码

C.承租人姓名(名称)

D.出租房屋的坐落及租赁用途

E.出租房屋的租金数额及交付时间

题型:问答题

阅读理解。

     The island Fiji has always been around me in my life. My parents met in Fiji when my father was a

teacher as a Peace Corps volunteer and my mother a student. They taught me about its people, culture,

foods and religious beliefs.

     At the age of two, I made my first trip across the Pacific Ocean to Fiji. My mother and I made that

trip unexpectedly because my grandma was ill and longed to see her American granddaughter. Although

I have few memories of that first trip, I do remember grandma braiding(编辫子) my hair every day. The

brush gliding through my hair is a feeling I will treasure forever because she passed away soon. I returned

to America when I was five years old. This time I had a brother, Martin, who was two.

     I resisted my third trip to Fiji when I was 15, being a teenager who did not want to spend the summer

away from friends. It was this trip, however, that made me realize that Fiji is not just a place to visit but a

part of who I am. The smells and sounds and sights came back to me, but the best part was getting to

know my relatives.

     Vishal was one cousin I quickly bonded with(与…合拍). Born two days before me, I had only

known him through pictures before. Though raised oceans apart in different cultures, we talked and

laughed about everything from American sports to Fijian dancing. I was able to form close ties with all

my cousins, and when I talk about them now, it's as if I have known them my whole life. Spending time

with them helped me understand the traditions and values my mother grew up with. Hospitality (热情)

and care and respect for family members are central values in Fijian culture.

     I truly enjoyed learning about my roots during this trip. Fuji is just like a second home, and I will never

forget the time I have spent there.

1. From the passage, we can learn that ________.

A. the author's parents had been classmates before

B. the author had lived in Fiji for about five years

C. the author had no memories of her grandma

D. people value family in Fijian culture

2. The author resisted her third trip to Fiji because_________.

A. she didn't want to separate from her brother

B. she didn't know her cousins there very well

C. she didn't want to separate from her American friends

D. her grandma had passed away

3. Which of the following is TRUE about Vishal?

A. He is younger than the author.

B. The author had met him on her first trip to Fiji.

C. He and the author had lots of common interests.

D. He and the author held different opinions about Fijian culture.

4. What's the best title for the passage?

A.  My Trips to Fiji

B. Discovering My Fijian Origins

C. My Understanding of Fijian Culture

D.  My Memories of Fiji

题型:问答题

人类最好的天堂和最舒适的伊甸园就是我们赖以生息、繁衍的地球。______我们并不否认可能有外星人的存在,______即便有外星人的话,也是他们已经在外星进化和适应了千万年或上亿年,已经适应了太空和他们那个星球的环境,正如人类用了千万年或上亿年的时间才适应了地球的生活。______把探索太空想象成今后进入太空是家常便饭或移居太空生活,那就等于要费力去开拓人类另外的栖息地,几乎是另一种进化的从头开始,因而可能性也几乎是零。
依次填入横线处正确的一项是( )。

A.即使 然而 只要
B.但是 因为 所以
C.不是 而是 要是
D.尽管 但是 如果

题型:问答题

《绝缘油颗粒数检测细则》,适用于()变电站的变压器、电抗器等充油电气设备。

A.6kV及以上

B.10kV及以上

C.35kV及以上

D.110kV及以上

题型:问答题

《混凝土结构工程施工质量验收规范》规定了混凝土结构工程施工质量验收的内容、方法,主要内容包括检验体系、检验类型、()。

A.检验等级

B.质量要求

C.验收程序

D.结构实体检验

E.同条件养护混凝土试件

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