- Create a new content type, or reuse existing one
- Add a new number/integer field for this content type (require Number module, shipped with CCK): go to admin/content/node-type/NODETYPE/fields (D6) or admin/structure/types/manage/NODETYPE/fields (D7)
- Select the format "Selected answer" for this field in the "Display fields" section: admin/content/node-type/NODETYPE/display (D6) or admin/structure/types/manage/NODETYPE/display (D7).
- Go to the Q/A settings page (admin/settings/question_answer in D6 and admin/config/question_answer in D7) and select the content type/field name above.
- That's all!
You can set the expiration time for each question. After this time, the reply with the most votes will be automatically selected as the answer.
- Go to the Q/A content type, create a new field "duration"
- Type: Integer (D7: List (Integer))
- Widget: Select list
- In the configure page, enter prefined time in second, for example (unlimited, 1 day, 7 days and 30 days):
- Select the format "Remaining time" for this field in the "Display fields" section: admin/content/node-type/NODETYPE/display (D6).
- Go to the Q/A setting page, select this field.
- Install VotingAPI module and another module, for example, vote_up_down (don't forget to enable "vud on comments").
- Go to permissions page, allow anonymous to vote on comments.