Unlike the short flights of the shuttle and earlier spacecraft, which carried sufficient power in fuel cells and batteries, a permanently orbiting space station will have to generate its own electricity.
                    
                
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                Athe short flights of the shuttle and earlier spacecraft, which carried sufficient power in fuel cells and batteries
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                Bthe shuttle and earlier spacecraft, with sufficient enough power in fuel cells and batteries for their short flights
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                Cthe short flights of the shuttle and earlier spacecraft, which enabled them to carry sufficient enough power in fuel cells and batteries
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                Dthe shuttle and earlier spacecraft, which were capable of carrying sufficient power in fuel cells and batteries for their short flights
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                Ethe flights of the shuttle and earlier spacecraft, whose shortness allowed them to carry sufficient power in fuel cells and batteries
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