"And according to ABNT rules, the maximum distance to be travelled to the emergency exit should be 30 metres, " he added.

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The council says it allocated places to children living closest to the school, up to a maximum distance of 0.685 miles.

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The momentum argument gives an easy estimate of what this maximum distance is.

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That meant Button was able to lap at his maximum potential for his entire first stint, trailing the Toyotas at a few seconds' distance, while Vettel's pace was compromised in the early laps by Hamilton.

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"You'll arrive in a town - and there will be a signal sent to your car not to exceed a maximum speed, and you won't be able to, and distance to the car in front will also be controlled, " he said.

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