I want to pull in a value from a picklist froma custom Account field into a related custom Opportunity field.

Account = DOD,  Business Unit =  Federal.  Opportunity = "Army Procurement Project",  Account = DOD,
Business Unit = Federal.
 
I need the Opportunity Business Unit value to be automatically pulled from the Account Business Unit field where Account = DOD.  The Account Business Unit API name is Business_Unit_c.  The value "Federal" was selected on Account object from a picklist.

Help with the syntax and an example would be appreciated!  Thanks!

I want to pull in a value from a picklist froma custom Account field into a related custom Opportunity field.

Account = DOD,  Business Unit =  Federal.  Opportunity = "Army Procurement Project",  Account = DOD,
Business Unit = Federal.
 
I need the Opportunity Business Unit value to be automatically pulled from the Account Business Unit field where Account = DOD.  The Account Business Unit API name is Business_Unit_c.  The value "Federal" was selected on Account object from a picklist.

Help with the syntax and an example would be appreciated!  Thanks!