Jawabanmu

2014-03-24T22:52:20+07:00
K = 2 phi r = 2. phi . 50/phi = 100 cm 
jarak = 100 x 10 kali = 1000 cm = 10 m

10 m --> 2 sekon 
100 m --> .......?

x = 100/10 . 2 = 20 sekon
1 5 1