"It is always difficult with any shared space - there is always conflict when you have drivers and pedestrians sharing the same space, " he added.

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There is, after all, only so much floor space in any given department store.

ECONOMIST: Retailing

Here the maths is unambiguous - we have insufficient budget for the carbon we are already emitting and by the time shale gas is produced in any quantity (five to 10 years), there will be no emissions space left for it.

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And there is no waiting around, nor any risk of being lost in transit and trapped horribly in sub-space limbo.

ECONOMIST: Don��t look now, I��m teleporting

Mr. JONES: There's a point at which any manager in the space program has to decide how much effort is enough to ensure safety vs. how much more resources will have to be expended to get an incremental improvement in safety.

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