声程不小于1.6N后声场就进入()。A、近场区B、扩散区C、非扩散区D、盲区

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问题:

声程不小于1.6N后声场就进入()。

A、近场区

B、扩散区

C、非扩散区

D、盲区

考点:无损探伤工无损探伤工(中级)无损探伤工(中级)题库
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