Need help with RC-50

[Rick Walker <looppool@cruzio.com>]

I have a musical student who wants me to teach him about
his RC-50.  

Unfortunately, I don't have too much experience with this unit.

RC-50 users, would you kindly answer a couple of questions I have about 
this unit?


1)   Are all the synchronized three loops always the same length?

2)  If not,  can someone direct me to how to use this unit to create 
different lengthed (albeit
synchronized loops)?

3)  Does the RC-50 do double or half speed manipulations of the loop

4)   Does the RC-50  have any kind of feedback control of loops?


My assumption (not backed up by much)  is that this unit has three 
different loopers that
can be synchronized with each other.

5) is there any way to have two loops synced and a third loop random in 
legnth

6)  Does this unit have any UNDO features.

Thanks in advance for your help.