Current Attempt in Progress Sparkle Company uses job costing and applies overhead using an actual costing system using direct labour hours as the allocation base. This period's estimated overhead cost is $400,000, estimated direct labour cost is $500,000 and estimated direct labour hours are 25,000 . This period's actual overhead cost was $420,000, actual direct labour cost was $390,000, and actual direct labour hours were 20,000 . What is the overhead allocation rate? $21/ hour $10/ hour $16/ hour $18/ hour