Question 19 5 pts How many edges are incident at each vertex in an n-dimensional cube graph? O n2 O n-1 5 pts Question 20 In the directed graph with vertices [a,b,c,d) and edges lla blac).(a,d) (b,c) (b,d) (d.c) (c not a Hamiltonian cycle ) (?.b)) there is O True O False