"There's no hard and fast rule on whether age differences sink the love boat, " Singleton wrote.

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There is no hard and fast rule about how often and how long one must engage in self-affirmation for it to work.

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While there is no hard and fast rule, investors should look favorably upon companies that hedge at least 30% of their expected annual fuel usage.

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This is most certainly not a hard-and-fast rule, in general I've found it to be accurate.

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According to Robert Smith, the BBBC general secretary, there is no hard-and-fast rule preventing 28-year-old Robb from holding a licence.

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While not a hard-and-fast rule, she says, women are more likely than men to get swept into a partnership by personal affinity for someone without looking at the business reasons for partnership.

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The truth is that there can surely be no hard-and-fast rule for a country as diverse as America, 7% of whose population in a typical year will be exposed, according to Robert Ursano of the Uniformed Services University of the Health Sciences, to a traumatic event.

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There is no hard-and-fast decision rule or trigger mechanism to which he or she must adhere in deciding whether supply conditions in the oil market justify an intervention.

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