Intro and outro for 24 hour fitness revenue have been prepared, and Overview of 24 Hour Fitness,  has been already addressed. Now, continue to create content and reply in english language with captivating storytelling language style, formatted in HTML plaintext (ignoring tags like html, head, body).  Each text segment should be strictly within the opening tag <contentzza> and the closing tag </contentzza> for consistency of content structure and easy processing later. Focus the discussion specifically on:

							2. Revenue Streams of 24 Hour Fitness
- Identify the primary sources of revenue for the company.
- Elaborate on membership fees and their impact on overall revenue.
- Discuss additional services offered, such as personal training and classes, and their contribution to revenue.
							
							Expected Output:
							<contentzza>
							<h2>{Revenue Streams of 24 Hour Fitness}</h2>
							{intro paragraph}
							{explanatory paragraph}
							<h3>{Sub-topic}</h3>
							[detailed content here]
							</contentzza>
							
							With structure:
							- Content structure should be between <contentzza> and </contentzza> tags to facilitate later separation with pregmatch or suitable pattern.
							- <h2>{Main Title}</h2>: At the beginning, without numbers/embellishments, followed by an intro paragraph.                 
							- <h3>{Sub-topic}</h3>: Use direct, descriptive, and factual titles. Do not write questions or commands (such as how, what, explain, discuss, why, or other question phrases).
							- Before each list (<ul> or <ol>), include an intro paragraph explaining the context or importance of the points to be discussed.
							- Add to use html tag <ul>, <ol>, <table> for topic details with relevant intro.
							- Provide <blockquote> for important phrases/formulas.
							- Avoid repetition and questions in topics or subtopics, and unnecessary introductory phrases.
							- Avoid paragraphs that contain only one sentence, except within <ul> tags.

							Notes:
							- Use one <h2> at the beginning, avoid <ul>, <ol> tags or dash (-) for just one item.
							- Ensure information, including examples and data, is accurate and comes from reliable/verifiable sources.
							- Transform all questions into informative statements that represent the content of the sub-topic.
							- For content under <h3> tag, avoid paragraphs consisting of only one sentence.
							- No need for a conclusion or closing in the content. Avoid creating any sub-topics or closing paragraphs, as the outro is already prepared.
							- Avoid phrases like 'continuation of', 'further elaboration', etc.
							- For illustrations/images, provide in-depth and descriptive information without using image links. Do not ask me to do it. Avoid situations like this '[image...]' where you expect me to do it; I refuse. Additionally, you should be the one describing the image.							
							- For content involving predictions or estimates, include examples or real-life cases that are recognizable and relevant. This ensures the content is credible and relatable, grounded in actual data or real-life situations, in accordance with the context discussed.