W is a self-employed journalist and has written articles for a newspaper 'ABB' for some years. Two days ago W learned from a reliable source that the Investment Bank MCC was being investigated for fraud. The next day W wrote a short article about the Bank and sent it to the Editor of ABB. ABB had not requested the article from W. However, in previous dealings ABB had paid W $5,000 for such unsolicited articles. Two days after W sent his article to ABB, he received an email from its Editor, containing an offer of $15,000 for his recent article about MCC. One week after the Editor's email, ABB published W's article. ABB now denies the existence of a contract with W and refuses to pay him $15,000. Advise W on the following issues: (a) Whether there was an offer. (b) Whether there was any acceptance, assuming such offer existed.