where is the battery located.is it easy to change
The battery is in the driver's front fender in front of the wheel. It is directly below where the (+) and (-) terminals are in your engine bay. You will need to remove the wheel and the fenderwell splash shield to access it.
Here's a video for removing the Stratus battery - jacking up the car is important: http://www.carcarekiosk.com/video/1996_Dodge_Stratus_ES_2.4L_4_Cyl./battery/replace_battery