Problem
1. Find the value of the flags field (in hexadecimal) for an unauthoritative message carrying an inverse response. The resolver had asked for a recursive response, but the recursive answer was not available.
2. Analyze the flag 0x8F80.
3. Analyze the flag 0x0503. Is it valid?
4. Is the size of a question record fixed?
5. Is the size of a resource record fixed?