It is impossible to accurately assess their wealth because so much of it is hidden.
It is impossible to accurately trace the line between Van Gogh's art and his mental condition.
It remains impossible to accurately predict who will win the 113th US Open.
Inevitably, therefore, it's impossible to accurately predict with any certainty the long-term economic costs of avoiding or coping with the impacts of climate change.
"It's nearly impossible to accurately communicate dynamics and phrasing, although I grudgingly admit that it was a far better tool than I had anticipated".
He said it's impossible to accurately determine how many migrants are leaving Haiti and what percentage of them make it to shore.
For much of the history of brain research, it has been nearly impossible to accurately test ideas about how the brain works.
Asked about Mr. Sherman's figures, Mr. Weitzman said it was "impossible to accurately assess" them because the department had not followed proper procedures during the period audited.
Tesla declines to cite a price for battery replacement, saying on its Web site that it is "impossible to accurately forecast the cost of future battery replacements".
"We believe that we can understand and manage the credit risk of these companies," he said, "whereas it is impossible to accurately forecast and predict interest rates on a macro level".
"It is impossible to accurately assess the probability and severity of terrorist attacks," the company said, so such insurance can be issued conventionally only on a very limited basis.
