Despite Congress mandating all railroads be equipped with a Positive Train Control system by the end of the year, Chicago's Metra system isn't expected to reach that goal until 2019. Most commuter trains won't meet the deadline. M. Spencer Green/AP hide caption

toggle caption M. Spencer Green/AP

If kids head off to the park to play by themselves, are their parents failing to protect them? Or are they fostering independence? iStockphoto.com hide caption

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