The Garden Book Company advertised in a local newspaper "Just in, Herman's latest edition of 'The Flower Expert's Guide to Growing Great Flowers', hurry limited supplies available." In response, Barbara Bush called the Garden Book Company and asked what is the price for the book? The salesclerk, Julie, said the manager was out, but she thought the price might be $25 per book, but asked for Barbara's number and said she would get the manager to call Barbara back. Barbara gave her phone number and then hung up.

After hanging up the phone, Barbara wrote a letter to the Garden Book Company saying she accepted their price of $25 and was enclosing a cheque for two copies of the book (i.e. $50). She immediately mailed the cheque and letter at her local post office.

The next day the manager called Barbara and told her the price of the book was $30 per book. Barbara said, "Too late, I have already accepted your initial offer at $25 per book and I expect delivery." The manager replied there was no contract.

In contract formation terminology, what was the advertisement in the newspaper and why? Make sure you support your answer by applying the facts of the case