Sixty-seven percent of Americans are clueless about what Ivanka Trump and her husband Jared Kushner do for the Trump administration, according to a Business Insider poll published Tuesday.

Thirty-nine percent of respondents said they "definitely could not" describe their responsibilities, while 28 percent said they "probably could not" do so. Nineteen percent said they could "probably" or "definitely" not name their duties.

Ivanka Trump and Kushner are both unpaid advisers for President Donald Trump. Kushner leads the administration's initiative on a Middle East peace plan, while Ivanka Trump focuses on economic policy and issues affecting women and families.

Kushner has also helped in tackling the country's opioid epidemic.

Both helped Trump win his presidential campaign in 2016.

Kushner has been the target of intense criticism following The New York Times report that saidYou are here:

End-Permian mass extinction linked to sea sulphur saturation

The end-Permian mass extinction was the largest biotic catastrophe of the last 540 million years, resulting in the disappearance of >80% of marine species. The effects of such catastrophe were also particularly long, since a full biotic recovery only occured 4–8 million years after the extinction event. Marine paleochemistry seems essential to explain not only the triggers of the mass extinction but also the reason why the effects lasted so long.

This study focus on redox chemistry changes in the Panthalassic Ocean (which represented ∼85–90% of the global ocean area at the time) and analyses all four sulfur isotopes (32S, 33S, 34S, and 36S) for pyrite from the deep-sea sediments of western Canada and Japan, two of the only three