July $4$ Miller Company purchased $$31,000$ worth of merchandise, terms $2\frac{\%}{10},\frac{n}{30}$ from Christensen Inc.. The cost to Christensen of the merchandise was $$18,200.$

$12$ Miller returned $$2,900$ worth of goods not ordered to Christensen for full credit. The goods had a cost of $$1,700$ to Christensen.

$(3)12$ Miller paid the account in full.

a$.$ Entries on the books of Miller Company

b$.$ Entries on the books of Christensen Company