Num $13$: Prepare the journal entry GAO would record if GAO provides a combined oil change service and parts package to a customer on October $7.$ Assume GAO distinguishes Service Revenue from Sales Revenue arising from the sale of parts, it uses a perpetual inventory system for recording the cost of goods sold, and it collects cash the day the oil change is performed. $($If no entry is required for a transaction$/$event$,$ select $"$No Journal Entry Required" in the first account field.$)$ Record the receipt of service and sales revenues.

Record the cost of goods sold.