AirQual Test Corporation provides on-site air quality testing services. The company has provided the following cost formulas and actual results for the month of February: The company uses the number of jobs as its measure of activity. For example, mobile lab operating expenses should be $4,700 plus $31 per job, and the actual mobile lab operating expenses for February were $8,880. The company expected to work 140 jobs in February, but actually worked 144 jobs. Required: Prepare a flexible budget performance report showing AirQual Test Corporation's revenue and spending variances and activity variances for February. (Indicate the effect of each variance by selecting "F" for favorable, "U" for unfavorable, and "None" for no effect (i.e., zero variance). Input all amounts as positive values.)