Very short they ask you the standard questions, like what made you apply, what skills you have, and why you want to work there. Make sure you ask a lot of questions about the many different federal programs at the end.
I applied online. The process took 2 months. I interviewed at Tennessee State Government (Memphis, TN) in Apr 2017
Interview
Once you have completed an online application you will then receive an email either stating your application went through or it didn't. If your application was approved then they will send you a link to complete a survey of qualification questions to see if you meet them. If you do meet the qualifications you will then receive an email with a suggested interview time and date.
Interview questions [1]
Question 1
What do you know about the workforce opportunities here in this area?