、如图11所示,一个质量为m的人站在电梯上,电梯与水平面夹角为370,已知重力加

题型:计算题

问题:

、如图11所示,一个质量为m的人站在电梯上,电梯与水平面夹角为370,已知重力加速度为g,当电梯以a =g/2的加速度向上加速运动时,求电梯对人的支持力和人所受到的摩擦力。

考点:受力分析
题型:计算题

阅读理解。

     Plants are very important.  This is because plants can make food from air, water and sunlight.  Animals and man cannot make food from air, water and sunlight.  Animals can get their food by eating plants and

other animals.  Man gets his food by eating plants and animals, too.  So animals and man need plants in

order to live.  This is why there are so many plants around us.

     There are two kinds of plants: flowering plants and non-flowering plants.  Almost all the trees around

us are flowering plants.  You can know some trees from their flowers and fruit.  Non-flowering plants do

not grow flowers.  You can not see many non-flowering plants around you.

     If you look carefully at the plants around you, you will find that there are many kinds of plants.  Some

plants are large and some are small.  Most of them are green.  Thanks to the plants around us we can live on earth.

1. We need many plants around us because _______.

A. plants can grow easily

B. plants are green

C. we can get what we need from plants

D. we like all kinds of plants

2. There are so many plants around us because _______.

A. man doesn’t need any plants

B. most animals don’t eat plants

C. man and animals need plants to live

D. the earth will become more beautiful

3. There are _______ non-flowering plants than flowering plants around us.

A. much fewer

B. much more

C. much larger

D. much better

4. Which of the following does NOT come from a plant?

A. Basket.

B. Bread.

C. Cabbage.

D. Stone forest.

5. Which is the best title(题目) of this passage?

A. Plants around us

B. Man and Animals

C. Live on Earth

D. Food and Plants

题型:计算题

小溪流的歌

        一条快活的小溪哼哼唱唱,不分日夜地向前奔流,山谷里总是不断响着他的歌声,太阳出来了,太阳向着他微笑。月亮出来了,月亮也向着他微笑。在他清亮的眼睛里,世界上所有的东西都像他自己一样新鲜,快乐。他不断向他所遇到的东西打招呼,对他说:“你好,你好!”

1.小溪流的歌是什么?请和小伙伴讨论讨论。   

                                                                                                                                      

2.请用你的双眼去发现,这个世界上有趣的东西!把它告诉你的好朋友。

                                                                                                                                       

                                                                                                                                       

题型:计算题

子宫颈癌发病率仅次于()

A.外阴癌

B.子宫内膜癌

C.乳腺癌

D.黏液性囊腺癌

E.无性细胞瘤

题型:计算题

记账以后,记账凭证的借贷方向机对应关系()。

题型:计算题

临床诊断为Ⅳ期的乳腺癌患者,其最佳的治疗方案为()

A.乳癌根治切除术

B.扩大乳癌根治切除术

C.单纯左 * * 切除术

D.改良乳癌根治切除术

E.姑息性手术+化学治疗+放射治疗

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