50x50x5mm 40x40x4mm brackets mild steel cut structural galvanized iron metal slotted angles bar $505.00 - $545.00 Min. order: 5 tons 457mm pile steel sheet New U type 400x100mm steel sheet pile 12m sheet pile detachable made in China $550.00 - $600.00 Min. order: 5 tons hot dipped ...
200*200*16 91.50 ASTM-A500GRB,C,D America进口/国产 250*250*6.3 48.10 300*300*6.3 57.90ASTM-A500GRB,C,D America进口/国产 300*300*8 73.10 350*350*8 85.70 ASTM-A500GRB,C,D America进口/国产 350*350*10 106.00 300*300*10 57.90 ASTM-A500GRB,C,D America进口/国产 300*300*8 90.70 350*...
100x100x4mm Application Gas/Water Pipe Welding Line Type ERW Processing Service Bending, Welding, Punching, Cutting Product name Section steel shs rhs 100 x 200 x 8 price, shs rhs steel pipe 300x300 Material 200 Series/300 Series Surface ...
china hot sale carbon steel square pipe 150x150 130x130 300x300 erw hollow tubes $450.00 - $600.00 Min. order: 10 tons hot dip galvanized tube s235 jr 50 x 50 square tube 60 x 60 $500.00 - $550.00 Min. order: 10 metric tons 3 inch galvanized square tub...
解:(1)建立的线性规划模型为max Z 200x1 240x260x150x24200s.t.30x160x140x250x230004500x1,x2将其标准化max Z 200x1 240x260x150x2x34200s.t.30x160x140x250x2x4x530004500xi0,i 1, 2, ,5(2)甲生产 20 件,乙生产 60 件,材料和设备 C 充分利用, 设备 D 剩余 600单位。(3)甲上升到 1380...