Michael was browsing in a shop which has displayed Swiss knives for sale. He picked up a Swiss knife which had many features, and a very affordable price tag on it. He was holding the knife in his hands and admiring it when police officers in plain clothes stormed into the shop and apprehended him. They also apprehended the shop owner who was at the cashier's counter at the time.

Under the law, it is an offence to sell or buy weapons. Therefore, both Michael and the shop owner were arrested for violating this provision of law.

Assume that the Swiss knife is a weapon under the law. Please answer the following questions strictly from the point of view of contract law: -

1. a) The police are of the opinion that the display of the item with a price tag was an offer by the shop owner to sell the item. Applying and recognising the principles of Contract Law, what, in your opinion, was the legal nature of the price tag on the item?
2. b) At the point in time when the police officers came into the shop, state whether there was a contract for sale or not.
3. c) State whether there was an offence made out in the circumstances of the case or not.
4. d) Please explain your answer in (c) above by applying the elements of law of contract.