Kayaks, 7, poses for a picture holding toy gun in a camp where Christians displaced by Islamic State militants are living, in Irbil, Iraq, Friday, December 23, 2016. Iraq’s Christians are marking the holiday in his camp for displaced people with a sense of worry and despair, unable to return to their towns they were forced to flee two years ago by the Islamic State group’s onslaught. (Photo by Manu Brabo/AP Photo)

A woman takes selfie as municipal workers use cranes to lift carcass of Bryde whale at the Juhu beach, in Mumbai, India, Friday, January 29, 2016. Marine biologists in India were conducting an autopsy on the carcass of 35-foot long Bryde whale that washed ashore on a popular beach in the western city of Mumbai. The beached mammal which appeared to have died at sea two or three days ago was spotted on the beach Thursday by late evening walkers, who informed police. (Photo by Rajanish Kakade/AP Photo)

People look at a man, who residents said was killed by al Qaeda militants, hanging on a bridge in Yemen's southeastern city of Mukalla June 17, 2015. Al Qaeda militants in Yemen killed two alleged Saudi spies, residents said, accusing them of planting tracking devices which enabled the assassination of the group's leader in a suspected U.S. drone strike. (Photo by Reuters/Stringer)

In this October 21, 2015, file photo, a young man rides a hoverboard along a Manhattan street toward the Empire State Building in New York. More than 500,000 hoverboards are being recalled after reports that they can burst into flames. The Consumer Product Safety Commission said Wednesday, July 6, 2016, it has received 99 reports of battery packs in the two-wheel motorized scooters catching fire or exploding that causing burns or property damage. The recalled hoverboards were made by eight companies. (Photo by Kathy Willens/AP Photo)

A Bengal tiger licks a glass enclosure during a presentation of Bengial tiger cubs at the Malabon Zoo in Malabon City, north of Manila, Philippines, 14 July 2016. The Bengal tiger cubs, which were born at the zoo, are two months old and named “Tiger Duterte” and “Tiger Leni”. The Malabon Zoo has one of the largest private collections of exotic and endemic animals in the Philippines. (Photo by Mark R. Cristino/EPA)

A Hindu devotee lies on a road as the holy “Rath”, or the chariot of lord Jagannath, passed over her during the Rath Yatra, or chariot procession in Karachi, Pakistan, July 17, 2016. Ratha-jatra is derived from two Odia words ratha/rotho meaning “chariot” and jatra meaning “journey”. The festival involves an annual procession (journey) of a deity's idols. Other names for the festival include ratha jatra or chariot festival. (Photo by Akhtar Soomro/Reuters)

Sakakibara Kikai's engineer Go Sakakibara poses with the bipedal robot Mononofu during its demonstration at its factory in Shinto Village, Gunma Prefecture, Japan on April 12, 2018. Developed at Sakakibara Kikai, a maker of farming machinery, LW-Mononofu is a 28-feet tall, two-legged robot weighing in at more than 7 tonnes. It contains a cockpit with monitors and levers for the pilot to control the robot's arms and legs. (Photo by Kim Kyung-Hoon/Reuters)

Firefighters watch as an air tanker drops retardant while battling the Ferguson fire in the Stanislaus National Forest, near Yosemite National Park, California on July 21, 2018. A fire that claimed the life of one firefighter and injured two others near California's Yosemite national park has almost doubled in size in three days, authorities said Friday. (Photo by Noah Berger/AFP Photo)