Gourley Clinic uses client-visits as its measure of activity. During August, the clinic budgeted for 4,200 client-visits, but its actual level of activity was 4,270 client-visits. The clinic has provided the following data concerning the formulas to be used in its budgeting:

	Fixed element per month	Variable element per client-visit
Revenue		$41.00
Personnel expenses	$37,000	$12.20
Medical supplies	3,000	9.00
Occupancy expenses	8,200	3.00
Administrative expenses	7,000	.30
Total expenses	$55,200	$24.50

The activity variance for net operating income in August would be closest to:

$405 F

$1,155 F

$1,155 U

$405 U