Child admin manage only exchange on his site

Hi Friend,

I have 3 sites US, UK & Canada. UK & canada had Child domain. Exchange 2010 is installed on all the sites. I want to assing a permission so that child admin in UK & Canada site only manage exchange on their site.

Topology

Exchange 2010 SP1

Parent Domain: abc.com

Child Domain: in.abc.com

Site: US (parent domain with Exchange 2010 SP1)

UK - Child with Exchange 2010 SP1

Canada - Chid domain with Exchange 2010 SP1

Thanks & Regards,

Guddu