阅读下面短文,根据所给中文正确拼写单词，使短文意思完整。每空限填一词。(10分)

Before you go to another country, it is a great  【小题1】(帮助)if you know the language and some of the customs of the country. When people 【小题2】(见面)each other for the first time in Britain, they小题1:(说)“How do you do.”and shake hands. Usually they do not shake hands 【小题4】(在…以后)they haven’t met for a long time. Last year a group of German 【小题5】(学生)went to England for a holiday. Their teacher told 【小题6】(他们)that the English people hardly shake hands. So when they met their English friends at the station, they kept their hands behind their小题2:(背).The English students had learned that Germans shake hands as often as 【小题8】(可能),so they put their hands in front and got 【小题9】(准备)to shake hands with them. It made both of them 【小题10】(笑).

某钢筋混凝土灌注桩，桩径为0.9m，桩长21m，预估其极限承载力为4000kN，当采用高应变法承载力检测时，锤的重量宜为（）。

A.80kN

B.60kN

C.50kN

D.40kN