An inspecting and profiling web controller that costs $40,000 has a life of 8 years with a $5000 salvage value. The estimated annual operating and maintenance cost is $3700 per year. If use classical straight line depreciation method, fill in blanks below to correctly represent the equation for the cumulative depreciation at the end of year 4. (HINT: skip $ and comma symbols) Annual depreciation deduction in year k: dk = ( Blank 1 - Blank 2 )/Blank 3 Cumulative depreciation through year 4: d4* = Blank 4years x Blank 5depreciation per year.