G1+G2=20N
(m1+m2)g=20N
m1+m2=20N/(10N/kg)=2kg
m1=(7880kg/m³)* 1dm³=(7,88g/cm³) *1000cm³=788g
am tinut cont ca 7880kg/m³=7880*10³ g/(10³ ) *(10³)cm³=7880/10³g/cm3=
7,88 g/cm³
deci
788g+m2=2kg=2000g
m2=2000-788=1212g=1,212kg
densitate cub doi= m2 ([g]/V2[cm3}=1212/1000g/cm³=
1,212g/cm3=1212kg/m³