某电路中电场随时间变化的图像如图所示,能发射电磁波的电场是哪一种?( )

题型:选择题

问题:

某电路中电场随时间变化的图像如图所示,能发射电磁波的电场是哪一种?(       ) 

考点:电磁波
题型:选择题

玻片凝集试验()

A.只能检测抗原不能检测抗体

B.只能检测抗体不能检测抗原

C.既能检测抗原又能检测抗体

D.为半定量试验

E.不能用于ABO血型鉴定

题型:选择题

罗马法中的人格包括以下哪几项权利?()

A.自由权

B.市民权

C.继承权

D.家庭权

题型:选择题

阅读理解。

      Christmas was just a week away and I had five people left to shop for and only three dollars.

     "Let's set a price limit(限制)on our gifts this year," I suggested to my best friend Joanie.

     "That's a good idea,"Joanie agreed."How about nothing over five dollars?"

      "How about sixty cents?" I felt like the biggest cheapskate in the world.

     "I guess this is where I'm supposed to say it's not the gift but the thought that counts,"Joanie smiled.

     It is almost impossible to buy anything under sixty cents, so it was really going to have to be very small

gifts with very big thoughts.

     Finally, Christmas Day arrived. I gave my mother a candle with a note that said," You are the brightest

light in my life." She almost cried when she read the note.

     I gave my brother a wooden ruler. On the back of it I had painted,"No brother in the world could measure

up to (比得上) you." He gave me a bag of sugar and had written on it, " You ' re sweet."

     For Joanie, I painted a pair of shoes with a note that said, " No one could ever fill your shoes (代替你)."

She thanked me and said I always tickted (搔) her and made her laugh. 

     To my other two friends, I gave Annie a paper fan and a note on it,"I' m your biggest fan." I gave Helen a

calculator (计算器) that cost one dollar and I painted a message on the back,"You can always count on(依靠)

me." My mother knows she is the most important person in my life.

     My brother thinks I' m sweet. Joanie thinks I' m funny and make her laugh, which is important because her

dad moved away last year and she misses him and is sad sometimes.

1. When Christmas neared, the author worried that she _____.

A. had few friends to give her gifts

B. had little money to buy gifts for others

C. didn' t know what gifts her friends would like

D. didn' t have enough time to shop

2. The underlined word "cheapskate" in Paragraph 4 may mean a person who _____.

A. is the poorest in the world

B. buys the cheapest skateboards

C. spends as little money as possible

D. buys the cheapest things in the world

3.The author gave her mother a candle because it represents  _____.

A. her life

B. her mother' s life

C. her role in her mother' s life

D. her mother' s role in her life

4. What lesson can we learn from the passage?

A. It is an art to choose gifts.

B. It is the thought not the gift that matters.

C. How to choose cheap gifts.

D. Giving gifts improves friendships.

题型:选择题

飞行中发生紧急情况,机长认为需要执行紧急着陆时,应使用紧急联络信号呼叫乘务长,如呼叫系统失效,机长应使用“系好安全带”灯或旅客广播系统通知乘务长。()

题型:选择题

在TD-LTE中,以下哪些协议栈的速率最大()。

A.应用层速率

B.PDCH层速率

C.MAC层速率

D.物理层速率

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