Statistics on the problems that we got wrong and Bookmarking them?(especially for SAT)

If the problems we got wrong are counted in each category and if we can check it, it would be really nice.

It would also be nice if we could bookmark some questions that we got wrong so that we can review them later - maybe just before the big exam - would be great! 

By these ways, we can catch better what our weakness is! This will certainly help our exam preparation, especially the SAT!

Thank you so much for your help.