20 �绰
Ҫӡȫ
ġ˵:Ŵо仰˵:ŵʱ,˱㻥 仰˵ˡķ,ڸ,ڿ,...
֮ŵ,һ...
ΪΪͨŵý,ͨͲеŨ,ʵֹⲨ20 dB/km¼ͨŵ,״ѲάΪ...
202000Ǹ...
Ϲֱ: 330¹ֱ: 270 Ϲֱ: ¹ֱ: СԲֱ880
йô,Щϡ?
knknknNkufhmmimimnmnzbafwnmiڤmngĨmnGnunrޕniYrY...
ûиһĿ˺þʫ?
1894oó,֮ͭ㡶⾰ һ 1895سا,FԴʾꡣε...
ƤʲôҪˢ,Щע?
Ũ»ɫ(),Ч2%ƷǴ̼ԱȽϴ,ܻ,Ƥ,ܵƤ...
Ϊһ,ʲôijʶҪ֪?
3ΪһɣгзDZӴ̸ܴЦ֮䣬ʬ...
Aᡢˮᡢ,Щᵽôˢ?
һʲôˢ˵ǣˢлϷϽʣʹƤлøЧ ˢ᷽...
йϵ,жǿ?
һҪᶷţһʥ硣ͨްʤܡһʤ...
ÿ÷ʲô仯?
۲,ʶ,δ,Ʒó,úóԻؼ,·Ƭ,...