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) $68,000 2,600 hours Account billing (number of lines) $34,000 17,000 lines Account verification (number of accounts) $18,000 20,000 accounts Correspondence (number of letters) $10,000 1,400 letters During the month, the Northeast Office used 100 hours and the Midwest Office used 250 hours on account inquiries: What is the activity rate that would be used to assign account inquiry costs to these offices? (Round your answer to the nearest cent.) O A. $2.00 OB. $0.90 OC. $7.14 OD. $26.15