It depends on factors like:
- How complex or difficult your question is
- How many users are online
- The number of connections you have
It will also depend on the availability of a person with the knowledge and experience to solve your question or problem. There are some users who remain online for a few minutes, while others may be logged in most of the day. So, when you post a question, it may be answered in 5 minutes, or sometimes you may even have to wait for 5 days.
Once someone has answered your question, you will receive a notification via email.
It is advisable to check your spam folder regularly as some valid emails often get categorized as spam.