LinkedIn uses the because regular users access LinkedIn for free but you can upgrade individual upgrades range from $29 a month to use services such as the ability to direct email messages to LinkedIn users outside one's network.

freemium revenue model

Explanation:

Freemium revenue model -

According to this model,

It is the stage of the product, which is completely free and accessible by all people or users , is referred to as the freemium revenue model.

This basic level can act as a trial service, which can potentially get paid for various new and advanced service.

It helps the customers to have a jest of the goods or service, and then can insure if they want to have the advanced version of it or not.

Hence, from the given scenario of the question,

Linkedln act as a freemium revenue model.