question on discrete maths for computer science.

-Fully explain your answers for all questions. Graphs are always assumed to be simple

Q2. Find all d such that there exists a graph with six vertices whose degrees are 1,1,1,1,3, d. [6] Draw a graph for each such d. Q3. (a) How many graphs with five vertices {01, 02, 03, 04, 05} have exactly four edges? [2] (b) Find the number of graphs with five vertices {01, 02, 03, 04, Us} such that the vertex vi has [3] degree 3, the vertex vy has degree 2, and the vertices 03, 04, us have degree 1