Jawabanmu

Jawaban paling cerdas!
2014-09-08T11:53:27+07:00
Dik 
1 kg = 1000 gram
1 m^3 = 1.000.000 cm^3
1 km = 1000 meter
1 jam = 60 menit = 3600 sekon

Maka
1. 2,5 g/cm^3 = ( 2,5 / 1000) x 1.000.000 = 2500 kg/m^3
2. 40 km/jam = ( 40 x 1000) / 3600 = 11,11 m/s

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