The U tube in the figure contains two liquids in static equilibrium. The water of density ρw (1000 kg/m3) is in the right arm and oil of unknown density ρx is in the left arm. If l = 80 mm and d = 20 mm, then the density ρx of the oil is
1
1000 kg/m3
2
200 kg/m3
3
600 kg/m3
4
800 kg/m3