Battery on 2008 Mercedes-Benz C300 4MATIC

Although it sounds obvious its not where is the battery located on a 2008 Mercedes Benz C 300 4 matic the manual says under the hood ... but its not visible...help

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2 answers 1 comment
as you are facing the engine, the battery is located to your left (passenger's side) at the firewall and may be
hidden by a black plastic cover. some have one large battery and some have two batteries. if under 50,000 miles, it is still under factory warranty.
Thanks a million...
Where is the battery in a 2008 Mercedes Benz c300 4matic?