A sample of 21 minivan electrical warranty repairs for “loose, not attached” wires (one of several electrical failure categories the dealership mechanic can select) showed a mean repair cost of $45.66 with a standard deviation of $27.79. (a) Construct a 95 percent confidence interval for the true mean repair cost. (b) How could the confidence interval be made narrower? (Data are from a project by MBA student Tim Polulak.)

The following cost and inventory data are taken from the accounting records of mason company for the year just completed: costs incurred: direct labor cost $ 90,000 purchases of raw materials $ 134,000 manufacturing overhead $ 205,000 advertising expense $ 45,000 sales salaries $ 101,000 depreciation, office equipment $ 225,000 beginning of the year end of the year inventories: raw materials $ 8,100 $ 10,300 work in process $ 5,900 $ 21,000 finished goods $ 77,000 $ 25,800 required: 1. prepare a schedule of cost of goods manufactured. 2. prepare the cost of goods sold section of mason company’s income statement for the year.