UPS truck is seen in Washington March 5, 2014. United Parcel Service Inc, the world's largest courier company, said it would buy 1,000 propane-fueled delivery trucks and install 50 fueling stations in... more 
UPS truck is seen in Washington March 5, 2014. United Parcel Service Inc, the world's largest courier company, said it would buy 1,000 propane-fueled delivery trucks and install 50 fueling stations in the United States as it expands its already-large fleet of alternative-fuel vehicles. REUTERS/Yuri Gripas (UNITED STATES - Tags: TRANSPORT ENERGY) less 
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Reuters | Photo By YURI GRIPAS / REUTERS
Wed, Mar 5, 2014 3:55 PM EST