在平面直角坐标系中,设点P(X,Y)定义[OP]=|x|+|y|,其中O为坐标原

题型:填空题

问题:

在平面直角坐标系中,设点P(X,Y)定义[OP]=|x|+|y|,其中O为坐标原点,对于以下结论:①符合[OP]=1的点P的轨迹围成的图形的面积为2;
②设P为直线
5
x
+2y-2=0上任意一点,则[OP]的最小值为1;
③设P为直线y=kx+b(k,b∈R)上的任意一点,则“使[OP]最小的点P有无数个”的必要不充分条件是“k=±1”;其中正确的结论有______(填上你认为正确的所有结论的序号)
考点:直线的方程
题型:填空题

阅读理解。

     Deputy Agriculture Secretary Kathleen Merrigan sees an epidemic (流行病) sweeping across

     America's farmland. It has little to do with the usual challenges, such as flood, rising fuel prices

and crop-eating insects. The country's farmers are getting older, and there are fewer people standing in

line to take their place. National agricultural census (普查) figures show that the fastest-growing group of

farmers is the part over 65. Merrigan is afraid the average age will be even higher when the 2012 statistics are completed.

     Merrigan, a former college professor, is making stops at universities across the country in hopes of

encouraging more students to think about careers in agriculture. Aside from trying to stop the graying of

America's farmers, her work is made tougher by a recent blog posting that put agriculture at No. 1 on a

list of "useless" college degrees. Top federal agriculture officials are talking about the posting, and it has

the attention of agricultural organizations across the country.

     "There couldn't be anything that's more incorrect," Merrigan said. "We know that there aren't enough

qualified graduates to fill the jobs that are out there in American agriculture."

     In addition, a growing world population that some experts predict will require 70% more food

production by 2050, she said.

     "I truly believe we're at a golden age of agriculture. Global demand is at an all-time record

high, and global supplies are at all-time record lows," said Matt Rush, director of the Texas Farm

     Bureau. "Production costs are going to be valuable enough that younger people are going to have the

opportunity to be involved in agriculture."

     The Department of Agriculture has programs aimed at developing more farmers and at increasing

interest in locally grown food. The National Young Farmers' Coalition has also been pushing for state and

federal policy changes to make it easier for new farmers.

     Ryan Best, president of Future Farmers of America, has been living out of a suitcase, traveling

the country and visiting with high school students about careers in agriculture. The 21-year-old Best

hopes his message-that this is a new time in agriculture-will motivate the next generation to turn

around the statistics. "Never before have we had the innovations (创新) in technology which have

led to agriculture in this country being the most efficient it has ever been," he said. "There's really a place

for everybody to fit in."

1. What is the new challenge to American agriculture?

A. Fewer and older farmers.    

B. Higher fuel prices.

C. More natural disasters.      

D. Lower agricultural output.

2. Why is Merrigan visiting universities across the country?

A. To draw federal agriculture officials' attention.

B. To select qualified agriculture graduates.

C. To clarify a recent blog posting.

D. To talk more students into farming careers.

3. According to Matt Rush, American agriculture will provide opportunities for younger people

    because__________..

A. the government will cover production costs

B. global food supplies will be even lower

C. investment in agriculture will be profitable

D. America will increase its food export

4. What do the underlined words "to turn around the statistics" in the last paragraph mean?

A. To re-analyze the result of the national census.

B. To increase agricultural production.

C. To bring down the average age of farmers.

D. To invest more in agriculture.

题型:填空题

患者女,56岁,右侧耳鸣1年,听力下降3个月。

常见于神经纤维瘤病Ⅰ型的是()

A.牛奶咖啡斑

B.视神经胶质瘤

C.视神经脑膜瘤

D.双侧听神经鞘瘤

E.空眶征

F.外周神经纤维瘤

G.中枢神经多发脑膜瘤

题型:填空题

下列情况中会导致房地产价格上升的是( )。

A.上调贷款利率
B.收紧房地产开发贷款
C.开征房地产持有环节的税收
D.增加土地供应

题型:填空题

关于客户准入,下列说法正确的是()

A.严禁承接他行风险客户特别是从小贷公司、村镇银行、典当行等退出转至农信机构的客户

B.可以承接建设银行退出类风险客户

C.可以承接小贷公司退出类风险客户

D.可以承接村镇银行退出类风险客户

题型:填空题

将以下5个句子重新排列组合:
①天空的霞光渐渐地淡下去了
②最早出现的启明星在这深蓝色的天幕上闪烁起来了
③那突然显得高远了的天空则呈现出一片肃穆的神色
④深红的颜色变成了绯红,绯红又变成了浅红
⑤最后,当这一切红光都消失了的时候
排列组合最连贯的是( )

A.②①⑤④③
B.①④⑤②③
C.①②③⑤④
D.③①④⑤②

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