Celebrity: Nicole Richie

Celebrity: Kristen Bell

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Celebrity: Penelope Cruz

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Celebrity: Jessica Simpson

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Celebrity: Katy Perry

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Celebrity: Scarlett Johansson

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Celebrity: Elizabeth Taylor

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Forty-seven years ago today, the nation mourned the assassination of President John F. Kennedy. (Read more about his life and see the iconic photo captured at his funeral. Watch some of Kennedy's speeches.) We take a look at other world leaders who were assassinated or survived attempts made in the name of a nation, a religion or a cause.
Anwar Sadat
The Egyptian president was killed (how old was he?) after receiving this international award for an agreement with this former political enemy. The historic meetings were arranged by this man. Read some of Sadat's speeches.

Benazir Bhutto
This former prime minister of Pakistan (see photos of her) was killed after this event. How old was she? When she was elected, she was the first woman to accomplish this in modern times. Read some of Bhutto's speeches.

Archduke Franz Ferdinand
This European heir apparent was assassinated (how old was he?) in this capital city by this terrorist group. He died with this person, and their deaths were the catalyst for this world event. Read some of the archduke's famous quotes.

Julius Caesar
This Roman dictator, who was killed by these men on this date, supposedly said these infamous words to one his assassins. Read some more of his famous words.

Mahatma Gandhi
This well-known leader of India's independence movement, who advocated for this type of resistance to this empire, was killed by this person.

Pope John Paul II
The leader of the Catholic Church survived an assassination attempt by this man during this public event. The pope died several years later due to illness.

Yitzhak Rabin
The Israeli prime minister was killed in this manner for participating in this political process. How old was he when he died?

Fidel Castro
Assassination attempts on the life of this longtime Cuban dictator have become the stuff of legends, such as this one discussed in this film. The leader's failing health also has spawned death rumors.

Indira Gandhi
The prime minister of India was shot by these men while she was on her way to see this actor.

Pancho Villa
When this Mexican Revolutionary leader was killed in this year, photos of his death were widely circulated to confirm his demise.

Agathe Uwilingiyimana
The first female prime minister of Rwanda was assassinated along with her husband just before this incident, which horrified the world. A member of this tribe, she lived for only a day after these two men.

Michael Collins
The Irish revolutionary leader was assassinated in this manner during this national conflict.

Ronald Reagan
Shortly after he took office, an assassination attempt on the U.S. president was made by this man because of his obsession with this Hollywood star. The failed attempt critically injured this man, whose wife became an advocate for this cause.

Nicholas II
The last tsar of Russia was killed by this group during this period of conflict, but what continues to rivet the world is the killing of these members of the Romanov family.

The homecoming king. The cheerleader. The CIA intern? You may be surprised to find out what some celebrities were up to in high school and college.

Movie stars
Michael Douglas, who is fighting cancer and is expected to recover, is said to have held an unusual position in his school years. Answer.

Jamie Lee Curtis, who stars in a movie about high school frenemies, has said she was not the most popular girl in high school. Answer.

Sandra Bullock, an Academy Award winner and new mother, is said to have been a popular class clown in high school and dated a football player.

Politicians and judges
First lady Michelle Obama was salutatorian of her class and attended school with a famous daughter. Answer.

Supreme Court Justice Ruth Bader Ginsburg played this instrument and her mother reportedly died the day before her graduation. Answer.

Sen. John McCain was known by an interesting high school nickname and went on to join the Navy

TV stars
Reality TV star Nicole “Snooki” Polizzi battled an eating disorder and reportedly wasn’t nearly as wild as she is today. Answer.

Clip show host and sitcom star Joel McHale quit his college rowing team then bluffed his way into another sport. Answer.

Blair Underwood, star of a sci-fi drama, got some practice for his latest role back in high school.

Musicians
Madonna, who grew up outside Detroit, was a straight-A student and earned a college scholarship. Answer.

Country singer Darius Rucker, former front man for this band, was involved in his church and school choirs. Answer.

Tom DeLonge, guitarist for this rock band, was expelled in high school but later returned and graduated.

TV Journalists
Anderson Cooper, a CNN anchor known by this nickname, spent part of his senior year in Africa before heading off to Yale. Answer.

Former CBS news anchor Dan Rather, who now works for another network, was a member of the Caballeros social club. Answer.

“Good Morning America” host and breast cancer survivor Robin Roberts was a popular multi-sport athlete in Mississippi.

Comedians
Banjo-playing funnyman Steve Martin, who recently joined Twitter, spent his teen years doing something completely different. Answer.

Comedian and satellite radio host Rosie O’Donnell was also voted class clown. Answer.

“The Daily Show” host Jon Stewart, who recently held a highly anticipated and well-attended rally, has been cracking people up since high school.

For the most part, celebrities have their pick of whom they want to date. After all, being rich and famous tends to make you irresistible to the opposite sex. Yet despite their otherworldly hotness, impeccable style and killer bods, some celebs are still flying solo in the love department. So which celebs are currently on the market? Click through for a rundown of the 25 hottest singles.