瓣鳃纲贝类饵料主要是（）。

单词拼写

1. He __________ (假装)to be doing his homework when the teacher came in.

2. We were impressed by the ruins of an __________(古代的) building.

3. 31. Man should protect __________ (野生动物)for his own existence.

4. The amount of rain a__________(影响) the growth of crops.

5. Seeing him struggling in the river, we came to his         (营救) at once.

6. A __________ (音乐家)is a person who performs or writes music, especially as his/her job.

7.         Day(圣诞节) is December 25th.

8. The automobile caused a __________(革命) in our way of traveling.

9. He seized the great         (机遇) and got famous in the country.

10. He __________(代替) his brother as captain because his brother was ill.

化合物X(C₁₂H₁₃O₄Br)是一种重要化工原料，存在如下转化关系：

已知：①与官能团直接相连的碳原子称为α－C，α－C上的H称为α－H，易被取代。

②通常在同一个碳原子上连有两个羟基不稳定，易脱水形成羰基。.

根据以上信息回答：

（1）已知D能与碳酸氢钠反应生成二氧化碳，则D中官能团的名称是___________，检验A物质是否完全反应可选用的试剂是_______(填编号)。

①银氨溶液             ②氯化铁溶液     

③氢氧化钠的酚酞溶液   ④新制氢氧化铜的悬浊液

（2）B→E的反应类型是_____________。

（3）已知F在一定条件下可以发生加聚反应生成高分子化合物，写出E和足量NaOH的醇溶液加热反应的化学方程式___________________________________。

（4）C的同分异构体中遇氯化铁溶液显紫色，且能发生银镜反应的物质共有     种，请任写一种物质的结构简式______________。

供应链管理强调采用的思想和方法是( )

A．集成

B．分散

C．整体最优

D．局部最优

人体的皮肤、呼吸系统和肾脏都具有的生理功能是（　　）

A．呼吸功能

B．排出体内的废物

C．排出二氧化碳

D．排出水分和无机盐

A. per
B. your skin
C. any harm
D. diet
E. your knees and hips
F. appearance
G. your back

Going to bed late does harm to ______.