Select the best match for the following questions.

Options :.Approximation algorithm, 0.5, Exact algorithm, 2, Heuristic algorithm

1. Work well for small graph problems, but may become computationally intractable for larger problems
2. Can guarantee how good or bad the solution is compared to an exact algorithm
3. The traveling salesman problem does not have this type of algorithm
4. This type of algorithm does not have an error guarantee
5. If the maximum independent set in a graph is of size 10, an algorithm that will return for a complement graph a clique of size 5 in the worst case is said to have an approximation ratio of ...