How To Automatically Log User Who Approved a Transaction Record

Hello, I have a simple "Submit for Approval" and "Approved by Manager" process on a form in my "Transactions" table (see attached image.)

I'd like to record the user who sent the transaction for approval and also the manager who approved it.  The user who is editing the form would be the one who's info we would record.  IE - If "User A" is editing the form and clicks "Send for Manager Approval" we would want to capture "User A's" information in the User field.  Same for manager.

This would also help to better direct email notifications to the appropriate parties.

Is there a way to have Quick Base grab this info when the form is saved? 

Thanks for your help!

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Josh Collins
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