先规定相应的标准如年龄、性别、某种特征等，然后再规定抽样的数目，从总体中找出符合条件

发布时间：2017-06-14 23:03 │ 来源：www.tikuol.com

题型：单项选择题

问题：

先规定相应的标准如年龄、性别、某种特征等，然后再规定抽样的数目，从总体中找出符合条件的观察单位，非随机抽取样本，这种抽样方法称为

A．专家抽样

B．特征抽样

C．随意抽样

D．目标抽样

E．分层抽样

考点：卫生资格考试(中初级)全科医学主治医师社区卫生

题型：单项选择题

完形填空。
I first saw the baby panda when she was only 10 days old. She looked like a white mouse. We l her Xi Wang.It means "hope". When Xi Wang was born,she weighed 2 100 grams (克). Xi Wang drank her mother's milk for as 3 as 14 hours a day. When she was six months old,she started to eat bamboo shoots(嫩芽) and 4 .Eight months later,she was not a small baby panda 5 . She grew into a 6 young panda and weighed 35 kilograms.When Xi Wang was 20 months old,she had to look after herself 7 her mother had another baby. 8 ,it is very difficult for pandas to live in the wild.Here are some of the 9 that pandas like Xi Wang may have in the future: If hunters 10 a panda,they will kill it for its fur.If farmers 11 trees and forests, pandas will have no place 12 . When mothers leave baby pandas 13 ,people often take them away. People think that baby pandas need 14 . Pandas are in danger,so we should do our best to protect them.If we do _ 15 ,there will be no pandas in the world soon.
( )1. A. made ( )2. A. quite ( )3. A. many ( )4. A. leaves ( )5. A. any more ( )6. A. strange ( )7. A. though ( )8. A. Luckily ( )9. A. examples ( )10. A. catch ( )11. A. cut ( )12. A. live in ( )13. A. lonely ( )14. A. money ( )15. A. nothing	B. called B. mostly B. long B. vegetables B. at least B. weak B. until B. Suddenly B. ideas B. feed B. plant B. lived B. together B. help B. everything	C. told C. just C. lots of C. trees C. at most C. famous C. because C. Sadly C. matters C. have C. protect C. to live in C. alone C. clothes C. anything	D. kept D. hardly D. far D. chips D. no more D. healthy D. whether D. Especially D. problems D. eat D. water D. living D. happily D. family D. something

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A．1mol NH₃所含有的氢原子数为3N_A

B．常温常压下，22.4L氧气所含的原子数为2N_A

C．常温常压下，48g O₃所含的氧原子数为3N_A

D．1L 0.1mol/LNaCl溶液中所含的Na⁺为N_A

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A．3种

B．6种

C．9种

D．12种

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