单项选择题
(A)硝酸钾 (B)盐基淡黄 (C)过氯酸钾 (D)次甲蓝
(A)60%~65% (B)65%~75% (C)75%~85% (D)80%~95%
(A)5m/s (B)10m/s (C)20m/s (D)30m/s
(A)30° (B)40° (C)50° (D)60°
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