Let $$U = \{ 1,2,3\} $$. Let 2$$^U$$ denote the powerset of U. Consider an undirected graph G whose vertex set is 2$$^U$$. For any $$A,B \in {2^U},(A,B)$$ is an edge in G if and only if (i) $$A \ne B$$, and (ii) either $$A \supseteq B$$ or $$B \supseteq A$$. For any vertex A in G, the set of all possible orderings in which the vertices of G can be visited in a Breadth First Search (BFS) starting from A is denoted by B(A).

If $$\phi$$ denotes the empty set, then the cardinality of B($$\phi$$) is ___________

Which one or more of the following need to be saved on a context switch from one thread (T1) of a process to another thread (T2) of the same process?

Which one or more of the following options guarantee that a computer system will transition from user mode to kernel mode?

Which one or more of the following CPU scheduling algorithms can potentially cause starvation?