15. The Weedwacker Company manufactures two types of lawn trimmers: an electric model and a gas model. The company has contracted to supply a national discount retail chain with a total of 30,000 electric trimmers and 15,000 gas trimmers. However, Weedwacker's production capability is limited in three departments: production, assembly, and packaging. The following table summarizes the hours of processing time available and the processing time required by each department, for both types of trimmers: Electric Hours Required per Trimmer Gas Hours Available Production 0.20 0.40 10,000 Assembly 0.30 0.50 15,000 Packaging 0.10 0.10 5,000 The company makes its electric trimmer in-house for $55 and its gas trimmer for $85. Alternatively, it can buy electric and gas trimmers from another source for $67 and $95, respectively. How many gas and electric trimmers should Weedwacker make and how many should it buy from its competitor in order to fulfill its contract in the least costly manner? a. Formulate an LP model for this problem. b. Create a spreadsheet model for this problem and solve it using Solver. c. What is the optimal solution?