Q: A graph has vertices A,B,C,D with edges AB, BC, CD, DA, AC. Find degrees and verify handshaking. deg(A) = 3 (AB, DA, AC). deg(B) = 2. deg(C) = 3. deg(D) = 2. Σ deg = 3+2+3+2 = 10 = 2×5 edges ✓. (Even number of odd-degree vertices: A, C - always even count!)