The following is total monthly budgeted cost and activity information for the four activity centers in the billing department of Oregon Power Company: Fixed Activity Center Account inquiry Correspondence Account billing Bill verification Variable $79,808 $9,369 $150,000 $8,740 $163,000 $29,000 $86,000 $79,000 Cost Driver 3,200 labor hours 2,700 letters 2,500,000 lines 19,000 accounts In September, actual costs and activity were as follows: Activity Center Account inquiry Correspondence Account billing Bill verification Total Costs $243,623 $38,453 $236,906 $88,243 Driver Amount 3,220 labor hours 2,900 letters 2,520,000 lines 18,960 accounts Required Compute the flexible-budget variances for the following two activity cost items (round all answers to the nearest dollar and enter favorable variances as positive numbers and unfavorable variances as negative numbers): Account billing Correspondence