Commercial advertising refers to the introduction of the goods or services provided by the business operator or service provider, directly or indirectly, through a certain medium and form. Which of the following are not commercial ads? ['The self-employed owner, Mr. Sun, yelled in front of his booth. As a result, many customers were attracted to it and they paid for his clothes.', 'A hotel promoted on the radio, saying how low the room price and how good the service attitude is.', 'In order to increase the sales volume of a product, a company printed a lot of publicity materials by itself, and delivered these publicity materials to consumers from house to house.', 'An enterprise ordered 4,000 newspapers with the newspaper, and the newspaper gave the company a full-page position for the company to advertise its products for free.']