淬火层硬度，抗拉强度大于或等于785MPa的钢轨，布氏硬度应为（）

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问题单项选择题

淬火层硬度，抗拉强度大于或等于785MPa的钢轨，布氏硬度应为（）。

A.HB280～350

B.HB301～370

C.HB351～380

D.HB250～280

答案

参考答案：A

填空题

用 journey , trip , tour, voyage 及 excursion 填空。

①The____________from here to Beijing needs about 18 hours.

②They took the weekend___________to the seashore.

③She has gone for a___________ in Europe.

④She had a brief stay in Paris during her recent __________.

⑤Within less than an hour, she made three home.

⑧The merchants set out on a ________ to India.

⑦They will go on a business __________to America next month.

问答题简答题

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