函数y=x3-3x2-9x+5在区间[-4,4]上的最大值为( ) A.10 B.-

题型:选择题

问题:

函数y=x3-3x2-9x+5在区间[-4,4]上的最大值为(  )
A.10B.-71C.-15D.-22
考点:函数的最值与导数的关系
题型:选择题

I bent down in the shade under a sixty-foot-tall cactus(仙人掌), waiting for them to appear. The time was eight thirty in the morning. For seven mornings I had come to the same distant spot in the Sonoran Desert, in southern Arizona. I was here to watch the roadrunner, a small fast-running bird.

I spotted two birds under a bush with red flowers. The roadrunners rushed out from under it. The birds moved rapidly on long skinny legs. Their feathers were brown and black. Their tails were seven inches long. Roadrunners use the tail for balance when running.

That day, the roadrunners performed a courtship(求婚)dance. They ran in wild circles. Suddenly, one stopped and stood still, its round eyes full of light. The second bird took hold of a small stick off the ground and presented it to the first, a gift serving as a symbol of their partnership.

I returned to the spot each day, leaving bits of boiled chicken hoping they would return. Roadrunners eat snakes, lizards, mice, beetles, and spiders. Food is in short supply in the desert, so my offerings were welcome. The pair grew used to me.

Soon after the pair finished building their nest six white eggs appeared in the nest bowl. In about three weeks, six roadrunner chicks, skin as black as coal, cried for food. Their parents brought food such as fence lizards and stink bugs. They fed their young until they were a month and a half old.

Early one morning, a coyote(丛林狼)came around, nose to the ground, for fresh bird meat. The roadrunners fearlessly drove the coyote away, but it was soon back. After three attacks the coyote went away for good, tail between its legs.

I stopped watching the nest when the little roadrunners, at two months of age, were ready to live on their own. It was hard to break away from “my roadrunner family.” Whenever I see a roadrunner now, rushing over the ground, I say hello to it as an old friend.

小题1:The author went to the Sonoran Desert to       .

A.go on a tour of the desert

B.carry out research into some animals in the desert

C.make an observation about a kind of bird

D.enjoy an adventure in southern Arizona小题2:What can we learn about roadrunners from the text?

A.They have short tails and legs.

B.They move at a fast pace.

C.Their feathers are red and brown.

D.They don’t like boiled chicken.小题3:We can learn from the last but one paragraph that the roadrunners were        .

A.brave

B.clever

C.easily-frightened

D.lazy小题4:Which of the following would be the best title for the text?

A.How do roadrunners seek a partner?

B.My close friendship with roadrunners.

C.Roadrunner family in the Sonoran Desert.

D.How did I find roadrunners in Arizona?

题型:选择题

组织细胞增多症X最后可形成的疾病有()

A.肺纤维化

B.肺脓肿

C.反复发作的自发性气胸

D.肺结核

E.肺囊肿

题型:选择题

头颈肿瘤综合治疗中,强调计划性综合治疗,应用最广泛的是()

A.手术与化疗

B.手术和放疗

C.放疗和化疗

D.化疗和生物疗法

E.放疗和热疗

题型:选择题

广播电视事业对与取得应纳税收入有关的支出项目和与免税收入有关的支出项目原则上应分别核算,没有分别核算或确实难以划分支出的,经主管税务机关审核同意,纳税人可采取()确定应纳税收入总额应分摊的成本、费用金额。

A.税务机关核定法

B.分摊比例法

C.定额法

D.成本利润法

题型:选择题

人免疫系统中大量合成并分泌抗体的细胞是()

A.巨噬细胞

B.T淋巴细胞

C.致敏T细胞

D.浆细胞

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