If a Job Required Three Hours Each Time It Was

If a job required three hours each time it was done and was done twice annually, and cost the company $450.00 per hour each time it was done, what error was made by the estimator who determined the total annual cost to be $1,350.00?

A) failed to separate the material costs from labor
B) used the wrong per hour cost
C) divided instead of multiplied
D) used the incorrect number of times performed