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Workbook and Study Guide in ACC312 Introduction to Management Accounting Study Unit 4: Standard Costing and Variance Analysis g. Factory overhead variance using three-way method. AFOH P Less: BAAH P Spending Variance P BAAH P Ho Less: BASH P Efficiency Variance P BASH P Less: Standard FOH Volume Variance P h. Factory overhead variance using four-way method. P Less: Variable Spending Variance P P Less Variable Efficiency Variance P P Less: Fixed Spending Variance P Less Fixed Volume Variance P