6. (Drawing trees) (A tree is a connected graph without any cycle). (i) Find (draw) all trees which have exactly 7 edges and exctly 3 verices of degree 1. (ii) Draw all trees of: 1 vertex, 2 vertices, 3 vertices, 4 vertices, 5 vertices, 6 vertices, 7 vertices, but no vertex of degree 2. 7. (Drawing spanning trees) Definition: Let G be a graph. A spanning tree, T of the graph G is a sub- graph of G which contains all vertices of G and is a tree (that is it is connected and has no cycles). Draw all spanning trees of the graph from Figure 2. Find the number of spanning trees, T(G). Figure 2