The customer requests that you displace the combined capacity oftubing and annul

The customer requests that you displace the combined capacity oftubing and annulus of a well with 7 5/8 inch 26.4 lb/ft casingcontaining two strings of 2 3/8 inch 4.6 lb/ft tubing run to adepth of 4670 feet. What is the total number of barrels requiredto complete this job?