题干

某气体由氢气、一氧化碳、甲烷中的一种或几种组成。点燃该气体后,在火焰上方罩一冷而干燥的烧杯,烧杯内壁出现水雾;把烧杯迅速倒转过来,注入少量澄清石灰水,振荡,石灰水变浑浊。下列对该气体的推断不正确的是(  )

A:该气体可能是甲烷

B:该气体可能是两种气体的混合气

C:该气体可能是三种气体的混合气

D:该气体的组成共有四种可能性

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D

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    Maybe you have heard the expression “When in Rome, do as the Romans do”. So when you want to do business in France, you have to get to know French culture, to make marketing plans, and to run your business by local laws.

    ____The French take great pride in their language, so anyone who does not speak it may run the risk of being disrespected by his French colleagues or business partners. Also, another reason why learning French is important is that it is a great way to show every possible French business partner that you care and respect their country's culture and language.

    The first thing that you should do when meeting someone new is to shake his hand firmly and always look the person in the eye. In social meetings with friends, kissing is common.

    Use first names only after being invited to.____ The French will sometimes introduce themselves using their surname first, followed by their first name.

    Dress well.____ Your business clothing is a reflection of your success and social status. Always try to be tasteful and stylish. Women are advised to dress simply but elegantly.

    The French are passionate about food, so lunches are common in doing business m France, which usually consist of an appetizer, main meal with wine, cheese, dessert and coffee, and normally take up to two hours.____.

    Do not begin eating until the host says, “bon appetite”. Pass dishes to the left, keep wrists above the table and try to eat everything on the plate.____ This may suggest that you find the food tasteless.

A. The French draw information about people based on their appearance.

B. This is a time for relationship building.

C. Wearing make-up is practiced widely by business women.

D. Language should be the focus of anyone planning to do business in France.

E. Be careful with adding salt, pepper or sauces to your food.

F. Use Monsieur or Madame before the surname.

G. If eating in a restaurant, the person who invites always pays.