Section (3) Conduct by both parties which recognizes the existence of acontractis sufficient to establish acontract for salealthough the writings of the parties do not otherwise establish a contract. In such case the terms of the particular contract consist of those terms on which the writings of the parties agree, together with any supplementary terms incorporated under any other provisions of this Act.In summary, if merchants want to change the terms of an agreement, those changes usually go through, unless they are explicitly rejected, cause significant changes to the deal, or the original offer says no changes are allowed. Explain the above in layman terms?