Jawabanmu

2014-06-24T17:20:07+07:00
T = 2/3 . 20 = 40/3
f = 1/T = 3/40 = 0,075 Hz

3/2 λ = 0,6
λ =0,4 m

v = λ . f = 0,4 . 0,075 = 0,03 m/s
1 5 1
2014-06-24T20:54:26+07:00
Panjang gelombang = 60 : 1.5 = 40 cm / 0.4 m
cepat rambat nya = 60 : 20 = 3 cm / 0.03m/s

maaf kalau salah