A rigid block of mass M is supported by three symmetrically spaced rods as shown in figure. Each copper rod has an area of 750 mm^2; E = 120 GPa; and the allowable stress is 75 MPa. The steel rod has an area of 1100 mm^2; E = 200 GPa; and the allowable stress is 150 MPa. Determine the largest mass M which can be supported. M Copper 145 mm Steel Copper 200 mm 145 mm A 12,857.23 kg B) 25,800 kg C 21,629.71 kg D 15,900 kg