A visitor takes in a view of the downtown district from Twin Peaks on Friday, January 9, 2015, in San Francisco. (Photo by Marcio Jose Sanchez/AP Photo)

Bolivia's president Evo Morales holds his scared staffs of power during a blessing by Aymaran spiritual guides, in a traditional ceremony at the archeological site Tiwanaku, Bolivia, Wednesday, January 21, 2015. Morales is set to begin a new term Thursday, that will make him the Andean nation's longest-serving leader, riding high on a wave of unprecedented growth and stability. (Photo by Juan Karita/AP Photo)

David Pena poses for a photograph with his Lada 2101 built in 1979 on a street in Havana February 9, 2015. Getting parts from the United States is cheaper than in Cuba, where state-run stores sell them at four times the cost, said Pena, a mechanic and president of the Russian Car Club in Havana who drives a souped-up, sporty red 1972 Lada 2101 that he fixed himself. His own Lada has a Fiat engine and an extra Alfa Romeo carburetor. (Photo by Enrique De La Osa/Reuters)

Children play on an abandoned car near a protest, which is against the dissolution of Yemen's parliament and the Shi'ite Muslim Houthi militia's tightening grip on power, in the southwestern city of Taiz, February 13, 2015. (Photo by Mohamed al-Sayaghi/Reuters)

A Tibetan man stirs butter tea made for the arriving guest during the function organised to mark Losar or the Tibetan New Year at a Tibetan Refugee Camp in Lalitpur February 19, 2015. Tibetans across the world marked the arrival of the New Year with prayers and festivities. (Photo by Niranjan Shrestha/AP Photo)

In this Tuesday, March 17, 2015 photo, a French military plane takes off from the flight deck of the French Navy aircraft carrier Charles de Gaulle in the Persian Gulf. Aircraft aboard the French carrier are flying bombing and reconnaissance missions as part of a U.S.-led coalition targeting Islamic State militants in Iraq. (Photo by Hasan Jamali/AP Photo)

U.S. Air Force wounded warrior, Capt. Sarah Evans, jumps rope in a gym in San Antonio, Texas. Evans was diagnosed with cancer while deployed to Afghanistan and was medically evacuated back to the United States where her leg was amputated. (Photo by Master Sgt. Jeffrey Allen/U.S. Air Force)

A female Syrian soldier from the Republican Guard commando battalion drives a tank during clashes with rebels in the restive Jobar area, in eastern Damascus, on March 25, 2015. The female battalion, which was created nearly a year ago, consists of 800 female soldiers who are positioned in the suburbs of the Syrian capital where they monitor and secure the frontlines with snipers, rockets and machine guns. (Photo by Joseph Eid/AFP Photo)