maximum edges

Consider a simple undirected graph of 10 vertices. If the graph is disconnected, then the maximum number of edges it can have is __________.

The maximum number of edges in a bipartite graph on $$12$$ vertices is _________.

Maximum number of edges in a n - node undirected graph without self loops is

Maximum number of edges in a planar graph with $$n$$ vertices is _______ .

The maximum number of possible edges in an undirected graph with a vertices and $$k$$ components is _________ .