41.   However, it permitted the space agency to design a spacecraft that uses less fuel, making it smaller and cheaper to launch by hundreds of millions of dollars.

42.   Hybrid systems use less fuel and produce fewer emissions than diesel engines.

43.   If it were not destroyed, the fuel could be used to build thousands of nuclear warheads or possibly fall into the hands of terrorist groups or rogue states.

44.   Images of the burning Hindenburg are called to mind whenever critics assail proposals for using hydrogen fuel in automobiles.

45.   In a conservation move, it would allow drivers who use alternative fuels to drive solo down carpool lanes.

46.   In a conservation move, it would allow drivers who use alternative fuels to drive alone down carpool lanes.

47.   In practical terms, this means that regular fuel may be used if maximum performance is not required.

48.   In the United States, efforts to use natural fuels like biomass have been stymied in part by relatively low prices for oil and natural gas.

49.   It has a gasoline engine, which uses more fuel than the more expensive diesel models.

50.   Many of the student designs would use fuels other than gasoline and power sources other than the internal-combustion engine.