已知:a、b、c是△ABC的∠A、∠B、∠C的对边,a>b,关于x的方程x2﹣2

题型:填空题

问题:

已知:a、b、c是△ABC的∠A、∠B、∠C的对边,a>b,关于x的方程x2﹣2(a+b)x+2ab+c2=0有两相等的实数根,且sin∠A:sin∠B=4:3,若△ABC外接圆面积为25 π,则△ABC的周长是 _________

考点:一元二次方程根的判别式三角形的内心、外心、中心、重心
题型:填空题

用英文数字填空。                

1. four + eight = ________
2. thirteen + seven = ________
3. seventy - fourteen = ________
4. sixty - thirteen = ________
5. forty-eight - twelve= ________6. seven + eight= ________
7. fourteen + sixteen = ________
8. eighty - sixteen = ________
9. eighty - forty= ________
10. ninety + five = ________                                              

题型:填空题

解释下列划线词语在文中的含义。

屋舍俨然(                 )                     阡陌交通(                 )

向所志(                 )                     病 终(                 )

其林(                 )                     便还家(                 )

处处之(                 )                     欣然往(                 )

有良田美池桑竹之(                 )    阡陌交通(                 )

率妻子邑人来此绝境(                 )    太守,说如此(                 )

如外人(                 )                      余人各复至其家(                 )

无论魏晋(                 )                      渔人甚之(                 )

题型:填空题

下列各句中,带横线字解释错误的是()

A.出不入兮往不反,平原忽兮路超远。忽:忽然

B.使君谢罗敷:宁可共载不?谢:问

C.明明如月,何时可掇?掇:拾取

D.三顾频烦天下计,两朝开济老臣心。顾:访问

题型:填空题

(B)

When I was six, Dad brought home a dog one day, who was called "Brownie". My brothers and I all loved Brownie and did different things writh her. One of us would walk her, another would feed her, then there were baths, playing catch and many other games, Brownie, in return, loved each and every one of us. One thing that most touched my heart was that she would go to whoever was sick and just be with them, we always felt better when she was around.

One day, as I was getting her food, she chewed up one of Dad’s shoes, which had to be thrown away in the end. I knew Dad would be mad and I had to let her know what she did was wrong. When I looked at her and said, "Bad girl," she looked down at the ground and then went and hide. I saw a tear in her eyes.

Brownie turned out to be more than just our family pet, she went everywhere with us. People would stop and ask if they could pet her. Of course she’d let anyone pet her. She was just the most lovable dog. There were many times when we’d be out walking and a small child would come over and pull on her hair. She never barked or tried to get away. Funny thing is she would smile. This frightened people because they thought she was showing her teeth. Far from the truth, she loved everyone.

Now many years have passed since Brownie died of old age. I still miss days when she was with us.

Some people got frightened by Brownie when she ().

A. smiled

B. barked

C. rushed to them

D. tried to be funny

题型:填空题

合成终止法测DNA序列时,不用的DNA聚合酶是()。

A、DNA聚合酶I

B、DNA聚合酶II

C、TaqDNA聚合酶

D、Klenow片段

E、测序酶

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