What was the name of the volcanic stone native to italy used by the romans before concrete was used on the building scene?

The name of the volcanic stone was tufa and travertine. It was a native stone to Italy and was used by the Romans before using concrete for buildings. This was used in order to make the buildings looked like Greek marble. it was dedicated to God Portunus who was a divine that was associated with keys, harbors, and livestock. It also gave a topographical position of the buildings which were located near the ancient river of Harbor City of Rome.

martin luther king (1929-1968) was an activist for the african american rights, mr. king has a profile of a kind leader that built a tenacity, respect and full of hope future. he was an activist through civil disobedience and no violence pressure mechanisms. he tried to build a more egalitarian and fair society. his efforts carried a reivindication message of the civilian rights to every west corners. for that reason, he won the nobel prize in 1964.

a stronger central government  

its what they are