a scale ranking ten minerals from softest to hardest; used in testing the hardness of minerals. Define DENSITY: A measure of how much matter there is in a given amount of space.
Jerusalem is a hilly city so the altitude varies but it is approximately 750 Meters (2,500 feet) above sea level.
The Burj Dubai was renamed the Burj Khalifa after its inauguration in 2009, with a completed height of 829.8 m (2,722 ft). This graphic is probably from before the tower was completed.