Assume you have a digraph with 5 vertices (A, B, C, D, and E) and ...

[Yi-Chen]

Assume you have a digraph with 5 vertices (A, B, C, D, and E) and 9 arcs. A is incident from C, D, and E; B is incident to D and E and incident from C; D is incident to C and incident from E.

How many cycles are there in the digraph that start and end at B?
◦ 0
◦ 1
◦ 3
◦ 2
◦ none of these

[wtf444]

2

[clippers!]

Assume you have a digraph with 5 vertices (A, B, C, D, and E) and 9 arcs. A is incident from C, D, and E; B is incident to D and E and incident from C; D is incident to C and incident from E.

Suppose that the vertices of the digraph represent individuals and there is an arc going from vertex X to vertex Y if and only if X "likes" Y. Which of the following statements [A), B), C), or D)] is not true?
◦ A and B do not like each other.
◦ B likes E but E does not like B.
◦ E likes A and D but does not like B or C.
◦ A does not like B, C, D, or E.
◦ all of these statements are true.

[BAOCHAU2803]

all of these statements are true.