For? Frank’s Funky? Sounds, straight-line depreciation on the trucks is a A. fixed cost. B. variable cost. C. ?high-low cost. D. mixed cost. Posted on March 10, 2017 by admin For? Frank’s Funky? Sounds, straight-line depreciation on the trucks is a A. fixed cost. B. variable cost. C. ?high-low cost. D. mixed cost.