Jawabanmu

2014-04-28T12:52:47+07:00
KM = 2πr
          d
2. 3,14 . 2.5 mm
          9
= 1.744444444444444444444 = 1.75
2014-04-28T13:10:32+07:00
Keuntungan Mekanis = x  \pi x Jari Jari / Diameter

 \frac{2X3,14X2,5cm}{9}

= 1.75