Public question is a question that can be seen/answered by any astrologer.
Any astrologer can answer the question on a first come first served basis.
The fees depends on various factors, and count either go up or down with time. The fees will vary between 10-100₹. If the question is not picked up by any astrologer, then it is cancelled.
Public questions are seen by all astrologers, so you can definitely skip questions that are that are not worth your time.
At times two or more astrologer attempt to answer the same question simultaneously. In that case only the first answer is accepted; and the Save button disabled.
