Jawabanmu

2013-12-27T12:56:34+07:00
V=lamda kali f
v=100x40=4000m/s
2013-12-27T15:31:35+07:00
Dik : λ = 100 m
        f = 40 Hertz
Dit : V
Jb :
V = λ*f
   =100 * 40
   = 400 m/s