The weightless horizontal bar in the figure below is in equilibrium. Scale B reads 4.20 kg (N.B. as you know, the scale should read N, but no one told manufacturer). The distance in the figure (which is not scale) are: D1=10.0 cm, D2=9.5 cm, and D3=9.5 cm. The mass of block X is 1.00 kg and mass of block Y is 2.03 kg.