I think the quantity of ads shown in the Facebook Newsfeed should largely rely on various factors, such as the user's tolerance, the duration of their time spent on the platform, and the relevance and quality of the advertisements. Generally, it seems reasonable to display one ad for every 5 to 6 posts. This could help achieve a balance between providing a positive user experience and generating adequate advertising revenue. It is also essential to ensure that the ads shown are well-targeted and relevant to the user, as irrelevant advertisements can negatively impact the user experience and overall engagement. Nonetheless, it's important to continuously observe user behavior and modify the number of ads displayed as needed. For example, if analytics indicate a drop in user engagement or a rise in the abandonment rate of the platform, it may suggest that users are unhappy with the ad frequency, warranting necessary changes.