3) Nature Power Company uses the composite method and straight-line depreciation for its power plant equipment. Its Apple River plant, which began generating electricity January 1, 2018, had the following equipment: (5 points) Estimated Residual Equipment Life (Years) Cost Value Turbines Steam pipes Furnace 25 15 20 $4,500,000 $500,000 3,000,000 300,000 6,000,000 0 Required: 1. Compute the composite depreciation rate. 2. Compute the average service life 3. Compute 2018 depreciation