把甲数的小数点向左移动两位就是乙数的20%，那么乙数是甲数的______%．

Obama had learned to use chopsticks _____ before visiting China.   [ ] 

A. to eat                      

B. to eat with  

C. to eating with            

D. eating

大黄为常用重要，始载于《神农本草经》。

大黄的功效有（）

A.泻热通肠

B.逐淤通经

C.止血

D.凉血解毒

E.补中益气

F.回阳救逆

G.养阴生精

H.补火助阳

30岁男性病人，主诉成形黑粪2天，上腹隐痛，泛酸，来门诊检查，血压正常，心率86次／分，腹部无疼痛，疑病人溃疡病出血。

此检查，下列哪项不可能（）

A.红细胞计数，血细胞比容下降不明显

B.上腹部轻度压痛

C.肠鸣音增多

D.血红蛋白值进行性下降

E.腹腔穿刺有不凝血液

要求实验组与对照组在非实验因素方面尽可能一致的原则属于

A．重复原则

B．对照原则

C．均衡原则

D．抽样原则

E．随机原则

Originally introduced by Netscape Communications, (48) are a general mechanism which HTTP Server side applications, such as CGI (49) , can use to both store and retrieve information on the HTTP (50) side of the connection. Basically, Cookies can be used to compensate for the (51) nature of HTTE The addition of a simple, persistent, client-side state significantly extends the capabilities of WWW-based (52) .

49（）

A.graphics 

B.processes 

C.scripts 

D.texts