Its an accounting law question, can I please get detailed answers thank you very much !!!

QUESTION A: (100 MARKS)

Peter, a second-hand car dealer, purchased a car in the wholesale market for $15,000. Peter contracted to sell the car to David for $20,000, but David refused to take delivery of the car. Peter sued David for breach of contract.

Requirement:

(1)What damages can Peter claim? (40 marks)

(2)If Peter later sells the car to another purchaser for $18,000, what damages, if any, would Peter be entitled to? (60 marks)