Ned has just opened a barber shop in North Sydney and advertised on his website that he would provide an opening special of a full haircut and beard trim for $5 to the first 10 callers who rang the Barbers number.

Cam lives In Wollongong 80km south of Sydney but thought that this opening deal was very good and worth the trip down to North Sydney some 80km. He rang and said I am interested in your advertisement on your website and wish to make an appointment if I am one of the first 10. Ned told Cam he was one of the first 10 and booked an appointment for the following Tuesday. He would be the first person to have an appointment under this opening deal. Cam travelled to North Sydney from Wollongong and following his haircut and beard trim handed over a $5 note. Ned then realised that he had made a mistake and told Cam that it should have read $25 not $5 on the website. Ned told Cam that was a big discount anyway, as it normally costs $65 for a haircut and beard trim Cam was furious and refused to pay the extra $20. Advise Ned a) Can he sue Cam for the $20 as a mistake had occurred? b) What cases would you use to argue on behalf of Ned? c) What if Ned told Cam that he had made a mistake before the haircut and beard trim occurred and he refused to cut his hair at all? d) If Ned had an accident on the weekend before the haircut and trim which injured his hand so that he could no longer cut hair would the contract still be enforceable?