A portable speaker or ear buds-which to buy? This is a question for many teens as well as their gift-giving relatives. A similar question weighs on the minds of manufacturers, only their perspective relates to planning for production and sales for the upcoming year. Sheffield is one such manufacturer. Before setting firm budgets and targets for the coming year, company management reviews the year just ended. Key information related to last year is as follows. Set up a partial income statement through contribution margin for Shelfeld, recognizing appropriate amounts for the actual income statement, flexible budget, and master budget Use Excel to reference input cells for each calculation needed for these partialincome statements. Sales price variance Sales activity variance