单项选择题
A.50% B.60% C.98% D.97%
A.-20~0℃ B.-20~+30℃ C.-10~+50℃ D.0~+45℃
A.±15% B.±10% C.±5% D.±1%
A.1000CPM/(mR/h) B.1000C0PM/(mR/h) C.100CPM/(mR/h) D.10CPM/(mR/h)
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