A couple of WebSphere questions

Which memory pool does the JVM pull the memory from on the as400?  When you set
the min and max in for the jvm in the WebSphere admin console where does it pull
the memory from?  If you setup a WebSphere  memory pool does it pull the memory
from the base pool or the WebSphere pool? 
  
Some spec documents on your site specify that WebSphere needs 2Gig memory plus
1.5 Gig per site for test and 2Gig memory plus 2Gig per site.  What does the
document mean by site?  Each of the web applications running under WebSphere? Or
If you had multiple instances of WebSphere running? 

Thanks,
Susan Conger