Io's metallic core makes up approximately 20% of its mass. Depending on the amount of sulfur in the core, the core has a radius between 350 and 650 km (220â400 mi) if it is composed almost entirely of iron, or between 550 and 900 km (340â560 mi) for a core consisting of a mix of iron and sulfur.
In 1886, Karl Benz developed a petrol- or gasoline-powered automobile. This is also considered to be the first production vehicle as Benz made several other identical copies. At the turn of the 20th century electrically powered automobiles appeared but only occupied a niche market until the turn of the 21st century.
The automobile era began in earnest in 1908 when Henry Ford introduced his Model T to the American marketplace. Before 1908, only the well-to-do could afford cars. Thanks to Ford Motor Company, the purchase of an auto became possible for most everyone. The rackety sound of the Model T â chuck-a chuck-a â became a major part of the nationâs soundtrack.