Phoenix, Inc. uses activity-based costing and had the following estimated activity data for its Billing Department for the year Activities Estimated Costs Estimated Activity Account inquiry (number of hours) $66,000 2,000 hours Account billing (number of lines) $47,000 15,000 lines Account verification (number of accounts) $17,000 23,000 accounts Correspondence (number of letters) $14,000 1,400 letters During the month, the Northeast Office checked 12,000 lines of account billing and the Midwest Office checked 8,000 lines of account billing. What is the activity rate that would be used to assign account billing costs to these offices? (Round your answer to the nearest cent.) A. $4.40 B. $33.00 C. $3.13 D. $23.50