Four firms called Elm, Maple, Oak, and Cherry, produce wooden chairs. However, they also produce a great deal of garbage (a mixture of glue, varnish, sandpaper, and wood scraps). The first row of the table below shows the total amount of garbage (in tons) that each firm currently produces. The other rows of the table show the cost of reducing garbage produced by the first five tons, the second five tons, and so on. Elm Maple Oak Cherry Current production of garbage (in tons) Cost of reducing garbage by first five tons Cost of reducing garbage by second five tons Cost of reducing garbage by third five tons Cost of reducing garbage by fourth five tons Cost of reducing garbage by fifth five tons 20 40 60 80 $5,500 $6,300 $7,200 $3,000 $6,000 $7,200 $7,500 $4,000 $6,500 $8,100 $7,800 $5,000 $7,000 $0 $9,000 $8,100 $6,000 $9,900 $8,400 $7,000 Calculate the cost of requiring the Oak firm to reduce the weight of its garbage by one-fourth. Please format your answer as the numbers appear in the table (e.g. $7,000).