试题与答案

洁净空调系统制作风管的刚度和严密性,均按高压和中压系统的风管要求进行,其中洁净度等级

题型:单项选择题

题目:

洁净空调系统制作风管的刚度和严密性,均按高压和中压系统的风管要求进行,其中洁净度等级N1级至( )级的,按高压系统的风管制作要求。

A.N5
B.N7
C.N9
D.N11

答案:

参考答案:A

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