speyer medical clinic measures its activity in terms of patient-visits. last month, the budgeted level of activity was 1,140 patient-visits and the actual level of activity was 1,130 patient-visits. the cost formula for administrative expenses is $3.80 per patient-visit plus $21,000 per month. the actual administrative expense was $21,700. in the clinic's flexible budget performance report for last month, the spending variance for administrative expenses was: