Liquid Gold, Inc., transports radioactive waste from nuclear power plants to disposal sites around the country. Each plant has an amount of material that must be moved each period. Each site has a limited capacity per period. The cost of transporting between sites is given in the accompanying table (some combinations of plants and storage sites are not to be used, and no figure is given). Develop and solve a transportation model for this problem.

Cost to Site Plant Material S1 S2 S3 S4 Site Capacity P1 20,876 $105 $86 — $23 S1 285,922 P2 50,870 $86 $58 $41 — S2 308,578 P3 38,652 $93 $46 $65 $38 S3 111,955 P4 28,951 $116 $27 $94 — S4 208,555 P5 87,423 $88 $56 $82 $89 P6 76,190 $111 $36 $72 —

P7 58,237 $169 $65 $48 —