On March 1, Job 10 had a beginning balance of $500. During March, direct materials of $800 and direct labor of $300 were added to the job. Overhead is applied to production at a rate of 40% of direct labor. There are four units in Job 10. What is the unit cost? Oa. $850 Ob. $430 Oc. $492 Od. $312 O. None of these choices are correct