Bert said : "5. A wrong answer is better than indecision. Always answer a question. Never say I don't know or I don't mind or I don't care." Now, I don't know about that. I've found that if you "don't know", the best answer is that you'll reserve decision and subsequent explanation upon further analysis and consideration, even though you are given to the work already laid down in your research to date, which, unfortunately, was somewhat rushed due to the unforeseen workload increase and accompanying lack of scheduled resources, the shortfall for which could not be accomodated in the time provided. Of course, if you've the gift of gab, wing it.