方程x2k-5+y210-k=1表示焦点在y轴的椭圆时,实数k的取值范围是___

题型:填空题

问题:

方程
x2
k-5
+
y2
10-k
=1
表示焦点在y轴的椭圆时,实数k的取值范围是______.
考点:椭圆的性质(顶点、范围、对称性、离心率)
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进食油腻食物后右上腹剧痛,辗转不安常见于()

A.胃穿孔

B.胆石症

C.急性胃炎

D.急性胰腺炎

E.肝脓肿

题型:填空题

大黄的特征是()

A.断面淡红棕色至黄棕色,颗粒性

B.根茎髓部宽广,有星点环列或散在

C.气清香,味苦而微涩

D.嚼之黏牙,有沙粒感

E.加工过程中忌用铁器

题型:填空题

首字母填空

The worst traveler in the world was Paul of San Francisco. Once he(1) f____ from the U.S. to his hometown in Italy to see someone at home. The plane made a one hour stop to get oil at an airport in New York. Paul thought he was in Rome. (2)C____, he got off the plane.

When nobody was there to meet him, Paul thought maybe the heavy(3) t___ made his friends late. While looking for their address, Paul found many high (4)m___ buildings instead of old ones. He also found that many people spoke English but not Italian and that many street signs were (5)w_____ in English.

Paul knew very (6)l_____ English. So he asked a policeman in Italian the way to the bus station, He happened to meet a policeman who was also born in Italy and answered in the same (7)l____.

After twelve hours ‘ travelling round on a bus, the driver handed him over to (8)a_____ policeman. But this time, this policeman could only speak English. So Paul asked the policeman why the Rome police employed(雇佣) so many people who spoke English as policemen.

Paul didn’t (9)b____ he was in New York when he was told so. To get him on a plane to Italy, he was(10) s______ to the airport in a police car.

题型:填空题

“类推”的思维方式在化学学习与研究中经常采用,但有时会产生错误结论。下列类推结论中,正确的是(  )

A.由氢氟酸刻蚀玻璃可推知盐酸也能用来刻蚀玻璃

B.由Na2O中阴阳离子个数比为1︰2,可推出Na2O2中阴阳离子个数比为 1︰1

C.由钠与冷水剧烈反应,可推知钾也能与冷水剧烈反应

D.由“2Fe+3Br2=2FeBr3”反应可推出“2Fe+3I2=2FeI3”反应也能发生

题型:填空题

下列哪种药物不是Ⅰ类抗心律失常药物()

A.普鲁卡因胺

B.利多卡因

C.氟卡尼

D.莫雷西嗪

E.伊布利特

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