以下关于氟斑牙的描述哪项错误（） A.牙面呈黄白相间的花斑 B.可有釉质缺损 C.对

解下列方程，找出规律并加以证明：

（1）方程x²+2x+1=0的根为：x₁= _________ ，x₂= _________ ，x₁+x₂= _________ ，x₁x₂= _________ ；

（2）方程x²﹣3x﹣1=0的根为：x₁= _________ ，x₂= _________ ，x₁+x₂= _________ ，x₁x₂= _________ ；

（3）方程3x²+4x﹣7=0的根为：x₁= _________ ，x₂= _________ ，x₁+x₂= _________ ，x₁x₂= _________ ；

由（1）（2）（3）你能得出什么猜想？你能证明你的猜想吗？

不属于基金销售的禁止性规定的是( )。

A．以排挤竞争对手为目的，压低基金的收费水平

B．对风险的提示

C．采取抽奖、回扣方式销售基金

D．利用基金资产进行利益输送

I have a good memory of my grandfather，Jack. He was sitting in his armchair in the front room.

I sat next to him. We were reading aloud，our heads bent over the page in front of us，a finger marking the words；separated by seven decades，brought together by words. It's a common scene in British families；however，in our case，the usual order of things is reversed（颠倒）．Granddad had been blind since I was tiny，so I was reading to him.When reading aloud，people usually read something that's of interest to the listener. So I didn't read children's books；I read the sorts of things Granddad liked to hear about. Much of the vocabulary in Granddad’s reading material was far beyond me. When I met unfamiliar words，I'd spell them out.

Granddad would help me. It must have been painful for him to hear news；but he never hurried me along or complained. Our reading wasn't really about getting knowledge. It was a way for us to spend time together.

My grandfather wasn't always blind. He had been a good carpenter（木匠）．The first Christmas of my parents' marriage，he built my mother a bookcase，which now belongs to my son Jonah，providing a link between four generations.

I was a fortunate child；I spent a lot of time with my grandfather，and he opened the world to me in a particular way. Reading was our way of building a relationship that has had a lasting effect on me. In the school holidays，I sometimes accompanied him on trips to the seaside with the local association for the blind. This might seem strange，but I felt that my personal value was realized because I could finally do something for Granddad.

A decade later，I found a position in a nursing home，which reminded me of my early experiences；reading to senior citizens was a connection back to Granddad. More than simple conversation，reading aloud is a connection between two individuals and it can have a big emotional（情感的）effect on elderly people.

小题1:What can we know from the first paragraph?

A．The author's grandfather was born blind.

B．The author is seventy years younger than her grandfather.

C．The author often sat opposite to her grandfather while reading.

D．It's quite common in Britain that children read to their grandfathers.小题2:Why didn't the author choose to read children's books?

A．To expand her knowledge.

B．To make her vocabulary bigger.

C．To show off in front of her grandfather.

D．To satisfy the needs of her grandfather.小题3:How did the author feel during the trips with Granddad?

A．Proud.

B．Troubled.

C．Curious.

D．Embarrassed.

70岁男性，因慢性房颤合并肺部感染就诊，平时服用地高辛O．125mg／d。查体：血压104／58mmHg，脉搏144／min，体温39．2℃。心电图显示房颤，但无明显ST变化。针对其目前房颤合并心动过速，以下叙述，何者最正确

A．应立即安排做经食管心脏超声

B．应先考虑给予静脉注射地尔硫革

C．先给予静脉注射胺碘酮是有效而必要的选择

D．应先考虑立即同步电复律

E．目前不考虑针对其心动过速予抗心律失常药物治疗

营养不良性钙化