A prototype Rollkers transportation device is displayed during a press event at the Mandalay Bay Convention Center for the 2015 International CES on January 4, 2015 in Las Vegas, Nevada. The product is not a skate; it balances for you and when you place it on the bottom of your shoe, it gives you the ability for faster transportation based on walking. The balance CES, the world's largest annual consumer technology trade show, runs from January 6-9 and is expected to feature 3,600 exhibitors showing off their latest products and services to about 150,000 attendees. (Photo by Ethan Miller/Getty Images)

Plaster cast moulds of victims of the Mount Vesuvius eruption lie on a display table in a laboratory at Pompeii October 13, 2015. An expert team made up of archaeologists, radiologists, orthodontists and anthropologists began on September 2015 to use CAT scan technology (computerised axial tomography) to peer inside the plaster cast moulds of Pompeii's victims, in a study that has added more detail to previous findings. A 16-layer scan had to be used in order to penetrate the hardened plaster but the results showed up impressive skeletal remains and near perfect teeth. (Photo by Alessandro Bianchi/Reuters)

Model and new Victoria's Secret Angel Taylor Hill from Illinois (L) and model Megan Puleri from Ohio (R) walk the runway while singer Selena Gomez performs during the 2015 Victoria's Secret Fashion Show at Lexington Avenue Armory on November 10, 2015 in New York City. (Photo by Dimitrios Kambouris/Getty Images for Victoria's Secret)

A photographer takes pictures near an inflated Master Yoda character hot air balloon during the 33rd annual QuickChek New Jersey Festival of Ballooning at Solberg Airport Friday, July 24, 2015, in Readington, N.J. The festival which runs through Sunday, July 26, 2015, will feature as many as 100 balloons, including many large, shaped balloons of Darth Vader, an American Flag, a giant whale, a Panda Bear, and a baby dinosaur. (Photo by Mel Evans/AP Photo)

Renowned aerobatic pilots Sean D. Tucker, flying the Oracle Challenger III, and Jeff Boerboon, flying the Jack Link's Screamin' Sasquatch, take to the skies over EAA's 2015 AirVenture Oshkosh, on Monday, July 20, 2015 in Oshkosh, Wis. (Photo by Matt Ludtke/AP Images for Jack Link's)

Firefighters extinguish a fire in Kampar, Riau province on Indonesia's Sumatra island on August 13, 2019. Indonesian authorities are deploying thousands of extra personnel to prevent a repeat of the 2015 fires, which were the worst for two decades and choked the region in haze for weeks. (Photo by Wahyudi/AFP Photo)

An Israeli boy looks through the sight of a weapon during a display of Israeli Defense Forces (IDF) equipment and abilities at the West Bank settlement of Kiryat Arba, April 23, 2015, during celebrations for Israel's Independence Day, marking the 67th anniversary of the creation of the state. (Photo by Ronen Zvulun/Reuters)

French climber Alain Robert, also known as “Spiderman”, holds the flag of Nepal as he scales the Tour Montparnasse, a 210-metre (689 ft) building in central Paris, France April 28, 2015, to show support for the victims after the earthquake in Nepal. (Photo by Gonzalo Fuentes/Reuters)