设F(X)在(-∞，+∞)上是奇函数，在(0，+∞)上f'(x)<0，f"(x)>0，则在(-∞， 0)上必有( )。

A:f'<0，f"<0 B:f'<0，f">0 C:f'>0，f">0 D:f'>0，f"<0

Across the Deserts

　　The SaharaDesertis the largest desert in the world. It stretches across Africa fromSenegaltoEgypt. TheSaharaDesertis an unfriendly environment. During the day it"s very hot, and at night it’s sometimes very cold. It is also difficult to find water in theSahara.

　　In 2006, Kevin Lin, Ray Zahab, and Charlie Engle decided to do something very difficult. They made the decision to run across the Sahara Desert 4,300 miles (6,920km). It seemed impossible to do, but they wanted to try. The three men liked to test themselves, and this would be a very big test.

　　On the morning of November 2, Kevin, Ray, and Charlie started their trip across theSahara. Every morning they began running at 5:00. At11 a.m. they stopped and rested until 5 p.m. Then they ran again until 9:30 in the evening. Each day they ran about 40 miles (64 km). Every day it was the same thing. They got up and ran. They listened to music on their iPods, and they ran and ran.

　　Kevin, Ray, and Charlie needed to eat a lot of food during their trip. Most people need about 2,000 calories of food each day. Kevin, Ray, and Charlie needed between 6,000 and 9,000 calories every day. That"s a lot of food! They also needed to drink a lot of water.

　　The three men had some problems on their trip, and many times they wanted to quit and go home. It was often very hot (140°F/60°C) during the day, and the heat made them sick. Their legs and feet hurt. Sometimes it was very windy, and they couldn"t see. One time they got lost. But they didn"t quit. After 111 days, Kevin, Ray; and Charlie successfully finished their trip across theSaharaDesert. They hugged each other and put their hands in the water of theRed Sea. Then they ran to a hotel to take a long shower.

　　词汇：

　　Stretch / strɛtʃ / v. 延伸，伸展

　　Calorie / "kælərɪ / n. 卡(路里)，小卡，大卡

　　Quit / kwɪt / v. 停止，放

　　注释：

In the middle of the day: the men usually stopped running.

A:Right B:Wrong C:mentioned

Across the Deserts

　　The SaharaDesertis the largest desert in the world. It stretches across Africa fromSenegaltoEgypt. TheSaharaDesertis an unfriendly environment. During the day it"s very hot, and at night it’s sometimes very cold. It is also difficult to find water in theSahara.

　　In 2006, Kevin Lin, Ray Zahab, and Charlie Engle decided to do something very difficult. They made the decision to run across the Sahara Desert 4,300 miles (6,920km). It seemed impossible to do, but they wanted to try. The three men liked to test themselves, and this would be a very big test.

　　On the morning of November 2, Kevin, Ray, and Charlie started their trip across theSahara. Every morning they began running at 5:00. At11 a.m. they stopped and rested until 5 p.m. Then they ran again until 9:30 in the evening. Each day they ran about 40 miles (64 km). Every day it was the same thing. They got up and ran. They listened to music on their iPods, and they ran and ran.

　　Kevin, Ray, and Charlie needed to eat a lot of food during their trip. Most people need about 2,000 calories of food each day. Kevin, Ray, and Charlie needed between 6,000 and 9,000 calories every day. That"s a lot of food! They also needed to drink a lot of water.

　　The three men had some problems on their trip, and many times they wanted to quit and go home. It was often very hot (140°F/60°C) during the day, and the heat made them sick. Their legs and feet hurt. Sometimes it was very windy, and they couldn"t see. One time they got lost. But they didn"t quit. After 111 days, Kevin, Ray; and Charlie successfully finished their trip across theSaharaDesert. They hugged each other and put their hands in the water of theRed Sea. Then they ran to a hotel to take a long shower.

　　词汇：

　　Stretch / strɛtʃ / v. 延伸，伸展

　　Calorie / "kælərɪ / n. 卡(路里)，小卡，大卡

　　Quit / kwɪt / v. 停止，放

　　注释：

They sometimes felt sick because it was so hot.

A:Right B:Wrong C:mentioned

设f（x）在（-∞，+∞）上是奇函数，在（0，+∞）上f'（x）＜0，f"（x）＞0，则在（-∞，0）上必有（）。

A:f'＞0，f"＞0 B:f'＜0，f"＜0 C:f'＜0，f"＞0 D:f'＞0，f"＜0

若f(x)=-f(-x)，在(0，+∞)内f’(x)＞0，f"(x)＞0，则f(x)在(-∞，0)内______．

A:f’(x)＜0，f(x)＜0 B:f’(x)＜0，f"(x)＞0 C:f’(x)＞0，f(x)＜0 D:f’(x)＞0，f"(x)＞0

设f(x)在x=0处满足f’(0)=f"(0)=…=f⁽ⁿ⁾(0)=0，f⁽ⁿ⁺¹⁾(0)＞0，则（）。

A:当n为偶数时，x=0是f(x)的极大值点 B:当n为偶数时，x=0是f(x)的极小值点 C:当n为奇数时，x=0是f(x)的极大值点 D:当n为奇数时，x=0是f(x)的极小值点

设f(x)在x=0处3阶可导，且f’(0)=0，f"(0)=0，f"’(x)＞0，则______．

A:x=0是f(x)的极小值点 B:x=0是f(x)的极大值点 C:在点(0，f(0))的左、右邻域曲线y=f(x)分别为凹与凸 D:在点(0，f(0))的左、右邻域曲线y=f(x)分别为凸与凹

若f(-x)=f(x)(-∞＜x＜+∞), 在(-∞，0)内f'(x)＞0，且f"(x)＜0，则在(0，+∞)内有______．

A:f'(x)＞0，f"(x)＜0 B:f'(x)＞0，f"(x)＞0 C:f'(x)＜0，f"(x)＜0 D:f'(x)＜0，f"(x)＞0

设f(x)在x=0处满足f'(0)=f"(0)=…=f⁽ⁿ⁾(0)=0，f⁽ⁿ⁺¹⁾(0)＞0，则______．

A:当n为偶数时，x=0是f(x)的极大值点 B:当n为偶数时，x=0是f(x)的极小值点 C:当n为奇数时，x=0是f(x)的极大值点 D:当n为奇数时，x=0是f(x)的极小值点

　　五、根据以下资料，完成各题。　　

下面关于该市城乡居民人均每日时间利用情况说法正确的有（　）。（1）该市城镇居民和农村居民用于学习培训的时间一样多（2）该市城镇居民用于看电视的时间比农村居民少12%（3）该市城镇居民用于社会交往的时间比农村居民少

A:0个 B:1个 C:2个 D:3个