Can sql 2008 r2 and sql 2012 coexist on the same cluster node, and the right installing order?

Hi,

I have two questions about sql server cluster installation:

First,Can sql 2008 r2 and sql 2012 cluster instances coexist on the same cluster node, and two version instances  works?

Second, after i install a sql 2012 cluster instance on a node ,can i add a sql 2008 r2 cluster instance on the same node? or i must install  sql 2008 then install sql 2012

Many thanks.