Two questions about practice tests on Khan Academy

Hello,
I have two questions regarding the LSAT prep tests on Khan Academy.
1. How do I reset the full test I have already taken?
2. Are the scheduled time tests ones from the past LSAT? If so, is there a way for us to know which ones are which? I need to plan my studies accordingly. I don't want to take a timed test if it's one I have already studied before.

Thanks!