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You may be able to avoid a towing charge if it can be jump started. But if it will not jump start, then something other than the battery may be causing the problem.
Also, if you have not already been doing this, always switch the stereo unit to the Radio mode when you're finished driving, and then turn the stereo off manually before turning off the engine. These cars are known to continue feeding power to the stereo if it's left on when the engine is turned off, which can reduce the battery's life.