How to Default the Values under RSSP in Billing Distribution Row Summary based on another Value

Summary:

How to Default the Values under RSSP in Billing Distribution Row Summary based on another Value.
My requirement is:

• Upon selecting project, Expenditure Org should default based on the org of the project.
• Upon selection of the project number, default the Expenditure Type from the category selected on the 1st page of the requisition.
• Only display the task numbers available for the Project, exp org, exp type selected on the page.

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