Central Bookstore advertised a one-day sale of law and business books which are offered to be sold at a 40% discount. The bookstore had only limited copies in stock, and all the law books were sold within the first hour of the sale. During the rest of the day, 100 other students came in the sought to accept the bargain offer.

(i)What are the principles of a valid offer?

(ii)Explain whether Central Bookstore is bound by any contract.

Loban is the sole proprietor of Central Bookstore. He wrote Dr Ng Chee on 10 January and offer to sell some second hand books for $3,500. The offer was "open until 20 January". On 18 January Loban sold the books to Prof. King, a colleague of Dr Ng, for $5,000 and the books were then placed at their common room where they may visit from time to time. On January 19 Dr Ng send Loban a formal letter of acceptance.

(iii)What are the principles of a valid acceptance?

(iv)Can an offer be cancelled before acceptance? In this case is the offer validly revoked?