Pierre (owner) and Blake (builder) have been negotiating a fixed price multimillion-dollar construction contract for many months. Negotiations started slowly, and they often used the post to negotiate the contract, exchanging their views in letters. This suited them both, because there was no urgency as the construction project still needed council approval. When council approval was granted to proceed with the project, the dynamic of the negotiations had changed, there were more disagreements, and Pierre and Blake negotiated exclusively face-to face. Despite strained relations, the parties got quite close to an agreement, and Pierre made a final offer of the fixed contract price to Blake of $9.2 million. Blake asked for time to think. Blake now wants to accept the offer. Advise Blake if sending the acceptance by post would result in a contract (i.e. whether it will be a valid acceptance)