单项选择题
A.80mm B.90mm C.100mm D.70mm
A.30℃;40℃ B.40℃;50℃ C.30℃;50℃ D.40℃;40℃
A.1.0m B.1.1m C.1.5m D.0.5m
A.20~40m3/min B.50~60m3/min C.10~20m3/min D.60~70m3/min
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