Requesting help with Advanced Alert Manager

I am trying to create an alert using Advanced Alert Manager that will trigger an alert when all our Server Nodes have a Memory Load that is "equal to or greater than 75", except for our SQL Server and Exchange Server, which we want to trigger a separate alert when they have a Memory Load that is "equal to or greater that 85".

I am unsure how to create this alert and if this is best done with two separate alerts or one complex alert.  Any help with creating this alert would be greatly appreciated.

Thanks.