In 2016, smart office systems inc. (sosi) used 25,840 pounds of plastic (direct materials) to produce 8000 units as opposed to 2017 when sosi produced 8500 units using 27,840 pounds of plastic. the type of plastic sosi uses cost $5 per pound in 2016 and rose to $5.25 per pound in 2017. in comparing results for these two years, what would be the cost effect of growth for the plastic material? $8075 f $8479 u $8075 u $10,000 u