Undirected graph with four vertices possible?

Question

Mathematics

Hello!
Undirected graph with four vertices: a, b, c, d deg(a)=1, deg(b)=2, deg(c)=3, deg(d)=4
possible or not?
(no, why?)
deg - degree (degree)

Answer 1

You draw on paper 4 vertices a, b, c, d.
From vertex d draw 3 edges to a, b and c. Where to spend the fourth? To d - there will be a loop, to any of a, b, c - there will be a multiple edge. Unless otherwise stated, this is not allowed.
PS In general, you're some kind of stupid parasite and a beggar.

Answer 2