From Click on the My Teams Tab on the Left Navigation toolbar you will notice .
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Notice all active users (members) are listed. Go to the “Actions” column and you will notice that all assigned Admins have a green icon turned on. To add another member or user as Admin place your cursor over the Admin icon it will say “Make Team Admin” then click.
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Any and all users (members) can be assigned as Admin, therefore your Team can have 1 Admin, 5 Admins or 20 Admins, this will depend on your internal policies.