Listed below are several properties that may pertain to various methods for solving systems of linear equation. for each of the properties listed, state whether this quality more accurately describes direct or iterative methods.

1. the entries of the matrix are not altered during the computation.
2. a prior estimate for the solution is .
3. the matrix entries are stored explicitly, using a standard storage scheme such as an array.
4. the work required depends on the conditioning for the problem.
5. once a given system has been solved, another system with the same matrix but a different right- hand side is easily solve.
6. acceleration parameters or preconditioners are usually employed.
7. the maximum possible accuracy is relatively easy to obtain.
8. "black box" software is relatively easy to implement.
9. the matrix can be defined implicitly by its action on an arbitrary vector.
10. a factorization of the matrix is usually performed.
11. the amount of work required can often be determined in advance.