Given a document, find the main entity about whom the author is writing. Write the full name if mentioned in the text. Note that URLs in the text have been replaced with [Link].
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Question: After enduring one too many maddeningly slow boarding experiences  Jason Steffen a professor of physics and astronomy at the University of Nevada Las Vegas  began digging into the unexpectedly complicated mechanics of efficiently ushering passengers onto planes.
In 2008   Steffen  created a computer simulation to evaluate existing boarding methods and ultimately design what  he  claims is the most efficient option for getting restless passengers into their seats. The results were published several years ago in the Journal of Air Transport Management (summarized here).
In  his  research   Steffen  identified the two most common factors responsible for slowing the boarding process to a painful crawl:
In fact  the most routine boarding process â from back to front â is actually the slowest of them all   Steffen âs argues  Itâs even less efficient than boarding a plane in a completely random order.
 Steffen  claims that  his  proposed method  which minimizes the former issue and eliminates the latter  could significantly reduce boarding times  thus cutting down on overall door-to-door flight lengths  and ultimately saving airlines hundreds of millions of dollars a year.

Answer: Jason Steffen


Question: Washington (CNN)  Sen. Lindsey Graham  R-South Carolina   warned against a potential conflict with North Korea "if things don't change."
"If we have to go to war to stop this  we will "  Graham  told CNN's Wolf Blitzer on Tuesday. "If there's a war with North Korea it will be because North Korea brought it on itself  and we're headed to a war if things don't change."
 Graham 's comments on CNN's "The Situation Room" come amid rising tension between the US and North Korea  and on Tuesday  the Pentagon confirmed that North Korea had launched what the US military believes to be an intercontinental ballistic missile.
 Graham  clarified that  he  doesn't think war would be the best outcome but said the US won't let Kim Jong Un have the ability to strike America's mainland.

Answer: Graham


Question: Days after  actress Kim Cattrall  announced the untimely death of  her  brother   her  “Sex and the City” co-stars are putting aside their ongoing feud with  the actress  to give their condolences.
 Cattrall ’s co-stars Sarah Jessica Parker and Cynthia Nixon joined the chorus of hundreds who took to social media to show their support for  her  during this difficult time. As previously reported  the 61-year-old star asked  her  followers for help earlier this week when  her  brother  Christopher  went missing. Hours later   she  posted an image of  her  posing with  her  brother announcing that he had been found dead.
A post shared by Kim Cattrall (@kimcattrall) on Feb 4  2018 at 1:00pm PST
Parker was the first “Sex and the City” actress to comment on the post  sharing a brief note of condolence with  Cattrall .
Later in the day   Cattrall  posted a follow up in which  she  thanked both  her  fans and co-stars for their kind words.
"I would like to thank my fans  friends and my #SexandtheCity colleagues for the outpouring of support for  myself  and family over the past 72 hours."
The well wishes from the stars come as the entire cast of the hit HBO series is embattled in a very public war of words. As previously reported   Cattrall  told Piers Morgan that  she  was never anything but professional colleagues with the other girls on the show during an October 2017 interview.
“We’ve never been friends ”  she  said. “We’ve been colleagues and in some ways it’s a very healthy place to be because then you have a clear line between your professional life and relationship and your persona.

Answer:
Kim Cattrall