Setting up a dependent form

[coneal4187]

Vendor	Project	PO	Asset
Apples Galore	Fall 10	11	Green
Apples Galore	Fall 20	22	Yellow
Johnny Appleseed	Fall 10	54	Red
Johnny Appleseed	Fall 20	67	Pink
Johnny Appleseed	Fall 20	67	Peach

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I'm attempting to set up a "form" of sorts so that the user can select the vendor from a drop down and then the project if they'd like and then it would populate in a separate area the PO's and the assets associated with those PO's

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