X5 Dead

[jbny]

All,

My x5 just died, all electronics are dead no light nothing, I had to open the door with the key, now I hope this is a dead battery and I know its in the trunk, can someone tell me how I can open the trunk for a locked car, it seems strange that I cannot even open the other doors with the lever from the inside, I can only open the drivers door.
I will be looking up the manual now and if nothing works will either call in a tow or try to jump start it, please let me know if there is a way I can just replace the battery myself.

Thanks for your help