1. E, A, B, C, D


2.

A    B
|    |
C    D
     |
     E


3.

A: dfsnum = 1, lowlink = 1
B: dfsnum = 3, lowlink = 3
C: dfsnum = 2, lowlink = 1
D: dfsnum = 4, lowlink = 3
E: dfsnum = 5, lowlink = 3


4. {A, C}, {B, D, E}


5. Because Tarjan's algorithm needs only the outgoing edges from each vertex, while Kosaraju's needs both incoming and outgoing edges. In a web graph, only the outgoing edges are directly available; we'd have to make an in-memory copy of the graph that includes lists of both incoming and outgoing edges in order to apply Kosaraju's algorithm.