Surely efficiency is based on choosing any route where you can drive at the most efficient speed for fuel economy, i.e. not too fast (freeways/motorways) and not too slow (inner city traffic). Quickest will often be longer than shortest and most efficient will sit somewhere between the two.
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F25 xDrive20d SE __ professional multimedia package | dynamic package | climate package | 309s | xline | xenons | electric seats | folding mirrors | business speakers
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