What is the best explanation for the variances between actual costs and estimated costs. For this purpose, assume that the additional meters of material used in the job were spoiled, the factory overhead rate has proven to be satisfactory, and an inexperienced employee performed the work.

a$.$ The direct materials cost exceeded the estimate by $$40$ because $2$ meters of materials were spoiled.

b$.$ Management didn't provide enough direction to complete tasks on budget.

c$.$ The direct materials cost exceeded the estimate by $$320$ because $10$ meters of materials were spoiled. The direct labor cost exceeded the estimate by $$84$ because an additional $6$ hours of labor were used by inexperienced employees who worked for $$1$ less per hour. The factory overhead cost exceeded the estimate because an additional $$67$ of factory overhead was allocated because of the increase in direct labor.

d$.$ Cannot be determined from the information provided.

e$.$ The direct labor cost exceeded the estimate by $$130$ because an additional $6$ hours of labor were used by an inexperienced employee who worked for $$1$ less per hour.

Select the correct answer from the above choices.