The exact relationship between PEDs and interference has been difficult to pinpoint, A4A acknowledged.

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The story of Lanxiang illustrates the murkiness that makes it so difficult to pinpoint responsibility for computer attacks.

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"It is extremely difficult to pinpoint any exact area we are not satisfied with because the tires are not consistent enough, " continued Vettel.

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State archaeologists know of Indian Ovens, one of several local archaeological sites, but they say it's difficult to pinpoint which tribe would have used them.

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Honey is a complex substance, containing up to 800 compounds and its complexity means it has been difficult to pinpoint exactly how it kills bacteria.

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It is difficult to pinpoint how many people subscribe to white supremacist views, because the Internet allows people to follow the movement under the cloak of anonymity.

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The variance in comparative values between the two metals makes it difficult to pinpoint a magic ratio that suggests one metal is cheap or expensive relative to the other.

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There are many confounding variables, however, that affect the value of a business aircraft, and without considerable research it can be difficult to pinpoint the best aircraft for you.

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There are times during Jedi Destiny when you control a speeder, gun turret or X-wing fighter for battles, but the controls seem sluggish and make it difficult to accurately pinpoint shots.

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Whether other outbreaks have occurred because of contaminated soda machines is difficult to determine, because food-related illnesses are notoriously challenging to pinpoint, Godard said.

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