Auniform steel rod has mass 0.300 kg and length 40.0 cmand is horizontal. a uniform sphere with radius 8.00 cm and mass 0.700 kg is welded to one end of the bar, and a uniform sphere with radius 6.00 cm and mass 0.580 kg is welded to the other end of the bar. the centers of the rod and of each sphere all lie along a horizontal line.
how far is the center of gravity of the combined object from the center of the rod?

express your answer with the appropriate units. enter negative value if the center of gravity is toward the 0.700 kg sphere and positive value if the center of gravity is toward the 0.580 kg sphere.