Please answer with explanation for the STR (Slack Time Remaining)?

Problem 22-11 Bill Edstrom, managing partner at a biomedical consulting firm, has requested your expert advice in devising the best schedule for the following consulting projects, starting at the beginning of the day on February 2. points DESCRIPTION OF CONSULTATION CALL RECEIVED DUE DATE (CLOSE TASK LENGTH COMPANY DATE TIME OF BUSINESS) 1 3 days Novartis Corp. February 1 9 A.M. February 7 || 1 days Reardon Biotech February 1 10 A.M. February 6 Corp. Vertex III 2 day oy Pharmaceuticals February 1 11 A.M. February 8 IV 4 days OSI Pharmaceuticals February 1 1 P.M. February 5 The consulting firm charges a flat rate of $4,000 per day. All four firms impose fines for lateness, Reardon Biotech charges a $750-per- day fine for each day that the completion of the consulting work is past the due date; Vertex Pharmaceuticals, Novartis, and OSI Pharmaceuticals all charge a fine of $2.000 per day for each day late. Prepare alternative schedules based on the following priority rules: SOT, FCFS, EDD, STR, and another rule-longest processing time (LPT), which orders jobs according to longest assigned first second longest assigned second, and so on. For the sake of simplicity, assume that consulting work is performed seven days a week. a. Calculate the total costs (sum of the late fines) for each rule. X Answer is not complete. Costs Priority Rules SOT 12.000 12,000 10,000 FCFS EDD STR LPT 9.750