1A declaration of acceptance of an offer shall have effect only if it is communicated to the offeror within the time he has fixed or, if no such time is fixed, within a reasonable time, due account being taken of the circumstances of the transaction, including the rapidity of the means of communication employed by the offeror, and usage. In the case of an oral offer, the acceptance shall be immediate, if the circumstances do not show that the offeree shall have time for reflection.
2If a time for acceptance is fixed by an offeror in a letter or in a telegram, it shall be presumed to begin to run from the day the letter was dated or the hour of the day the telegram was handed in for despatch.
3If an acceptance consists of an act referred to in paragraph 2 of Article 6, the act shall have effect only if it is done within the period laid down in paragraph 1 of the present Article.