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There are many different greeting customs around the world. Here are some.
Chile(智利) People usually shake hands when they meet for the first time. When two women fist meet, they sometimes give one kiss on the cheek. They actually “kiss the air'' Women also greet both male and female friends with a kiss. Chilean men give their friends warm abrazos (hugs) or sometimes kiss women on the cheek.
Finland (芬兰)Finns greet each other with a firm handshake. Hugs and kisses are only for close friends and family.
Korea (韩国) Men bow slightly and shake hands to greet each other. Women do not usually shake hands. To address someone with his or her full name, the family name comes first, the first name.
The United States (美国) People shake hands when they are first introduced. Friends and family member often hug or kiss on the cheek when they see each other. In these situations, men often kiss women but not other men.
nZ(g)＋2W(g), 5 min末已生成0.3 mol W，若测知以Z浓度变化来表示的反应平均速率为0.03 mol·L－1·min－1，则上述反应中Z气体的反应方程式系数n的值是( )
