James Manufacturing had the following information available for July: Flexible Budget Variance Sales Flexible Activity Budget Variance ? 3,000U ? Actual Results 12,000 ? Master Budget $10,800F ? ? Units Sales revenue Less: Variable manufacturing costs Variable marketing and administrative Contribution margin $90,500 $95,000 ? $127,000 ? $ 4,500U ? $5,200F $ 41,000 $7, 1000 $60,000 ? ? What was James's activity variance for variable manufacturing costs