Salus征和Gunn征多出现在高血压视网膜病变的哪一级（） A.Ⅰ级 B.Ⅱ级 C

从税收的本质来看，税收是国家与纳税人之间形成的以国家为主体的( )。

A．社会财富分配活动

B．社会剩余产品分配活动

C．社会产品分配关系

D．社会剩余产品分配关系

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

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

     "That's a good idea," Joanie agreed. "How about something 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.

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

measure up to you." He gave me a bag of sugar and wrote on it, "You're my sweet sister."

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

thanked me and said I always tickled (使……高兴) 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 that cost one dollar and I painted a message on the back, "You can always count

on 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 go shopping

2. The underlined word "cheapskate" in Paragraph 4 probably    refers to 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 girl gave her mother a candle because it stands for________.

A.  the girl's own life

B. her mother's life

C. the girl's role in her mother's life

D.  the mother's role in the girl's life

4. What 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.

用酸度计测定溶液的酸度，若溶液的pH值为4左右，对酸度计进行校正时需选用的标准缓冲液是

A．邻苯二甲酸氢钾标准缓冲液(pH4.00)
B．磷酸盐标准缓冲液(pH6.86)
C．邻苯二甲酸氢钾标准缓冲液(pH 4.00)和磷酸盐标准缓冲液(pH6.86)
D．磷酸盐标准缓冲液(pH6.86)和硼砂标准缓冲液(pH9.18)
E．草酸三氢钾标准缓冲液(pH1.68)和磷酸盐标准缓冲液(pH6.86)

单位质量燃气所具有的（）是燃气的比容

A、密度

B、容积

C、体积

什么叫电感？电感的单位是什么？