A . 15~20Hz
B . 20~40Hz
C . 40~60Hz
D . 40Hz~10KHz
[单选题]噪音的频率范围在()。A . 15~20HzB . 20~40HzC . 40~60HzD . 40Hz~10KHz
[填空题] 可听声的频率范围在()之间。
[单选题]紫外线频率的范围在()。A . 1011~1012B . 108~109C . 1013~1014D . 1015~1016
[单选题]中频增益曲线的频率范围在()。A.250~1000hzB.2500~6000hzC.250~6000hzD.1000~2500hzE.250~9000
[单选题]高频增益曲线的频率范围在()。A.250~1000hzB.2500~6000hzC.250~6000hzD.1000~2500hzE.250~9000
[单选题]高频增益曲线的频率范围在()。A.250~1000hzB.2500~6000hzC.250~6000hzD.1000~2500hzE.250~9000
[单选题]中频增益曲线的频率范围在()。A.250~1000hzB.2500~6000hzC.250~6000hzD.1000~2500hzE.250~9000
[单选题]低频增益曲线的频率范围在()。A.250~1000hzB.2500~6000hzC.250~6000hzD.1000~2500hzE.250~9000
[单选题]低频增益曲线的频率范围在()。A.250~1000hzB.2500~6000hzC.250~6000hzD.1000~2500hzE.250~9000
[单选题]话音基带信号的传输频率范围在()。A .1MHZ~lOMHZB .3KHZ~6KHZC .8KHZ~10KHZD .300~3000HZ