Since one-foot wire mesh is sold at $30, with $120000, Melany can buy $120000/$30 = <<120000/30=4000>>4000 feet of wire mesh.
If Melany has to fence 5000 feet of the field and has 4000 feet of wire mesh, she will not fence 5000-4000 = <<5000-4000=1000>>1000 feet of the field.
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