This information relates to Alfie Co$.$

On April $5,$ purchased merchandise from Bach Company for $$27,000,$ on account, terms $\frac{2}{10},$ net $\frac{?}{30},$ FOB shipping point.

On April $6,$ paid freight costs of $$1,200$ on merchandise purchased from Bach Company.

On April $7,$ purchased equipment on account for $$30,000.$

On April $8,$ sold $$16,000$ of merchandise to Mozart Company on account, terms $2/10,$ net $30.$

On April $9,$ returned $$3,600$ of the April $5$ merchandise to Bach Company.

On April $14,$ Mozart Company returned $$500$ of defective merchandise.

On April $15,$ paid the amount due to Bach Company in full.

On April $17,$ received payment on account from Mozart Company.

a$)$ Prepare the journal entries to record these transactions on the books of Alfie Co$.$ using a periodic inventory system.

b$)$ Assume that Alfie Co$.$ paid the balance due to Bach Company on May $4$ instead of April $15.$ Prepare the journal entry to record this payment.