10 things you need to know today: April 22, 2016

Prince was found unresponsive in an elevator at his Paisley Park compound in Minnesota early Thursday morning, and pronounced dead after CPR failed. He was 57. An autopsy is scheduled for Friday to help determine the cause of death. Born Prince Rogers Nelson, the Purple Rain artist reportedly made a health-related emergency landing in his plane on April 15 and his representatives said he was battling the flu. Known for his genre- and gender-bending performances that transcended the boundaries of rock, pop, funk, and R&B, Prince's legacy includes earning seven Grammys, performing at the Super Bowl in 2007, and selling over 100 million records worldwide.

President Obama weighed in on Britain's coming referendum on whether the U.K. should exit the E.U. (a movement known as "Brexit") in an op-ed he wrote for The Daily Telegraph. Most of the article is dedicated to the "special relationship" between the U.S. and Britain, but Obama also tells Britain that "the U.S. and the world need your outsized influence to continue — including within Europe." As part of his visit to Britain on Friday, Obama will have lunch with Queen Elizabeth II at Windsor Castle, meet with Prime Minister David Cameron, and dine with Prince William, Duchess Kate, and Prince Harry at Kensington Palace.

Republican presidential candidates Donald Trump and Ted Cruz shared their opposing views Thursday on the North Carolina law that requires transgender individuals to use bathrooms in schools and government buildings that correspond to the sex on their birth certificate. Trump criticized the law, calling it "unnecessary," and said the state is now "paying a big price" due to boycotts. Cruz is supportive of the law, and tweeted that Trump "isn't going to defeat political correctness," and instead "bowed to it." He later added, "We shouldn't be facilitating putting little girls alone in a bathroom with grown men. That's just a bad, bad, bad idea."

As many as 170 diplomats are gathering in New York Friday to sign a landmark climate-change deal to curb greenhouse gas emissions. The signing ceremony, which U.S. Secretary of State John Kerry will attend, is expected to set an international diplomacy record for the most diplomats signing an accord on the first available day. Participating countries that don't sign Friday will have a year to do so; the Paris agreement will take effect once 55 percent of countries representing at least 55 percent of global emissions have signed on. The world's two biggest polluters, the U.S. and China, who together are responsible for 40 percent of global emissions, both plan to sign the agreement. (Editor's note: This item originally misreported where the agreement is being signed. It has since been corrected. We regret the error.)

At a security conference in London on Thursday, FBI Director James B. Comey said the bureau "paid a lot" to unlock the iPhone of San Bernardino shooter Syed Farook, "but it was worth it." Comey did not share the exact cost, just that it was more than what he will make in the remaining seven years of his 10-year contract as director, the Los Angeles Times reports. Comey earns a yearly salary of $183,000. The FBI has not revealed the name of the third party it hired to help them hack into the phone, and a law enforcement official has said the FBI did not make any major discoveries on the device.

President Obama said in a Thursday meeting in Saudi Arabia with the Gulf Cooperation Council that despite the landmark nuclear deal reached with Iran last year, he still has "serious concerns" about the country's behavior. Though the agreement may have "cut off every single one of Iran's pathways to a nuclear weapon," it didn't eliminate concerns about illegal Iranian arms shipments, ballistic missile tests, and "destabilizing acts," he added. Obama has promised Gulf leaders weapons and support to curb Iran's influence in the region, as he works toward establishing better cooperation in conflicts in the Middle East.

The U.S. suicide rate is rising steadily and sharply, hitting a 30-year high in 2014 after rising 24 percent since 1999, according to a federal study released Friday by the Centers for Disease Control and Prevention. Suicides have risen among all age groups except people 75 and older, and have gone up faster among women than men. There was a notable surge in Americans age 45 to 64, with the suicide rate for women in that group jumping 63 percent and men 43 percent. Researchers suggested the steady and rising rate could be due to abuse of prescription drugs like opioids and economic upheaval, especially for people without college degrees.

Clinton campaign chairman John Podesta told The Boston Globe on Wednesday that while men such as Housing and Urban Development Secretary Julian Castro, Sen. Cory Booker (N.J.), and Labor Secretary Thomas Perez have all been floated as her VP pick, it's not so simple. "We'll start with a broad list and then begin to narrow it. But there is no question that there will be women on that list," Podesta said. The remark sent the commentariat buzzing that progressive icon Sen. Elizabeth Warren (D-Mass.) could be the right choice. Still, some believe an all-female ticket would be a tough sell. "They can't handle one woman on the ticket; what makes you think they could handle two?” New York state assembly member Jo Anne Simon said.

MTV is bringing back its first weekly live music series in almost two decades and re-launching its MTV Unplugged performance series in an effort to put the "music" back in its music television moniker. "We are re-asserting our DNA," MTV president Sean Atkins said. "MTV has to be the network that gives voice to youth and gives artists a voice to speak to youth. Music is our muse." Along the lines of Total Request Live, the weekly music show Wonderland will host concerts in a loft in downtown Los Angeles. The network will also be bringing back Cribs via Snapchat, plus 14 new series including a music competition show.

Following the news of music legend Prince's death, everyone from President Obama to the Minnesota Twins paid tribute to The Purple One. "The world lost a creative icon... nobody's spirit was stronger, bolder, or more creative," President Obama said in a statement. The New Yorker turned its cover purple in honor of the music legend, while Minnesota sports teams and The Late Show with Stephen Colbert added purple to their stadium and set, respectively. Jennifer Hudson, while starring in The Color Purple, led the cast in an encore tribute to Prince, performing "Purple Rain" for the audience.