Answer: It was the border between Texas and Mexico
Explanation:
Iran voted by national referendum to become an Islamic republic on 1 April 1979 and to formulate and approve a new theocratic-republican constitution whereby Khomeini became supreme leader of the country in December 1979. The revolution was unusual for the surprise it created throughout the world.
According to history-World.org"<span>The Spread Of </span>Islam<span>, The </span>Islamic<span> state expanded very rapidly after the death of Muhammad through remarkable successes both at converting unbelievers to </span>Islam<span> ... successfully established the new </span>faith through conversion and conquest of ... consolidating their power throughout the Arabian peninsula and began<span> to launch" all over the world by the book Quran which is a holy book from Allah to straight people to the right path, and Islam growth very fast because the followers are really strict to their tradition from the prophet Muhammad Peace Upon Him.</span>
Answer:
Mohs hardness, rough measure of the resistance of a smooth surface to scratching or abrasion, expressed in terms of a scale devised (1812) by the German mineralogist Friedrich Mohs. The Mohs hardness of a mineral is determined by observing whether its surface is scratched by a substance of known or defined hardness.
Related Topics: hardness
To give numerical values to this physical property, minerals are ranked along the Mohs scale, which is composed of 10 minerals that have been given arbitrary hardness values. The minerals contained in the scale are shown in the Table; also shown are other materials that approximate the hardness of some of the minerals. As is indicated by the ranking in the scale, if a mineral is scratched by orthoclase but not by apatite, its Mohs hardness is between 5 and 6. In the determination procedure it is necessary to be certain that a scratch is actually made and not just a “chalk” mark that will rub off. If the species being tested is fine-grained, friable, or pulverulent, the test may only loosen grains without testing individual mineral surfaces; thus, certain textures or aggregate forms may hinder or prevent a true hardness determination. For this reason the Mohs test, while greatly facilitating the identification of minerals in the field, is not suitable for accurately gauging the hardness of industrial materials such as steel or ceramics. (For these materials a more precise measure is to be found in the Vickers hardness or Knoop hardness) Another disadvantage of the Mohs scale is that it is not linear; that is, each increment of one in the scale does not indicate a proportional increase in hardness. For instance, the progression from calcite to fluorite (from 3 to 4 on the Mohs scale) reflects an increase in hardness of approximately 25 percent; the progression from corundum to diamond, on the other hand (9 to 10 on the Mohs scale), reflects a hardness increase of more than 300 percent.
