stat problem

In a friendship network, each node represents a person, and an edge between two nodes represents a friendship between two people. Ex) in this picture, they have a friendship network with 5 nodes and 7edges. O Consider a friendship network with r nodes. (Your answers should be in terms of n) 1. How many total possible edges could there be? (Hint: Think of how many pairs of nodes you can form. 2. How many total possible networks are there? (Hint: Think of each edge as being either on or off.)