Journalize entries for the following related transactions of Lilly Heating & Air Company: $($If an amount box does not require an entry, leave it blank.$)$

a$.$ Purchased $$48,000$ of merchandise from Schell Co$.$ on account, terms $\frac{2}{10},\frac{n}{30}.$

Accounts Payable$-$Schell Co$.$

b$.$ Paid the amount owed on the invoice within the discount period.

c$.$ Discovered that merchandise with an invoice amount of $$9,600$ purchased in $($a$)$ was defective and returned items, receiving credit.

d$.$ Purchased $$7,800$ of merchandise from Schell Co$.$ on account, terms $\frac{n}{30}.$

e$.$ Received a refund from Schell Co$.$ for return in $($c$)$ less the purchase in $($d$).$