Specifically, she needs someone who knows how to use certain types of computer sottware $($e$.$g$.,$ Google Web Designer$).$ She knows Jon, who is an expert in Dreamweaver. She does not know Jon very well, as he is someone she contacts solely for computer questions, and he only contacts her about a class they have together. In sum, they know each other a little bit, so they do not have to put much effort into maintaining their relationship. What network concept is Sarah and Jon's relationship an example of$?$

All of these answers are correct

Centralized network

Weak ties