Which of the following statements are TRUE?

1. The problem of determining whether there exists a cycle in an undirected graph is in P.

2. The problem of determining whether there exists a cycle in an undirected graph is in NP.

3. If a problem A is NP−Complete, there exists a non-deterministic polynomial time algorithm to solve A.

Let $${\pi _A}$$ be a problem that belongs to the class NP. Then which one of the following is TRUE?

Let S be an NP-complete problem and Q and R be two other problems not known to be in NP. Q is polynomial time reducible to S and S is polynomial-time reducible to R. Which one of the following statements is true?

The problems 3-SAT and 2-SAT are