Chapter 9 In class problems 1. The College of Engineering recently released an RFP to construct a third-story floor o top of the Industrial Engineering Wing. Separate contractors proposed two me Method I will use lightweight expanded shale on a metal deck with open web jo steel beams. For this method, the costs will be $14.100 for concrete, 36000 for me decking, $4300 for joists, and $2600 for beams. Method 2 will construct a reintor concrete slab costing $5200 for concrete, $1400 for rebar. $2600 for equipment rentals and $1200 in expendable supplies. Special additives will be included in the lightweig concrete that will improve the heat-transfer properties of the floor. If the energy costs will show a savings for Method I will be $600 per year and for method 2 will $1200 per year. In addition, the added Maintenance expense of another floor for method I will be $1200 per year and for method 2 $2500 per year. Which one is more attractive? Use an interest rate of 6% per year, a 20-year study, and the conventional B/C method. method 1:27,000 method 2:10,400