Wayland Corporation's static planning budget for April appears below. The company bases its budgets on machine-hours. Budgeted number of machine-hours 6,500 Supplies (@ $9.00 per machine-hour) $58,500 Power (@ $1.00 per machine-hour) 6,500 Salaries 85,800 Equipment depreciation 7,150 Total $157,950 In April, the actual number of machine-hours was 6,600, the actual supplies cost was $64,040, the actual power cost was $7,070, the actual salaries cost was $88,300, and the actual equipment depreciation was $7,430. The spending variance for power cost for the month should be?