They operate, maintain or repair geothermal power plants and commercial and residential geothermal heating installations. (googled this for you)
The leaders who spread Islam after Muhammad's death were Abu Bakr, Umar, Uthman, and Ali. If you want the answer from a website, I suggest going here
--> http://peopleof.oureverydaylife.com/led-islamic-world-after-muhammad-died-7743.html <-- I hope this answer helps you.
Primary political powers rests with the government.
Option A.
<u>Explanation:</u>
Socialism is a political, social, economic philosophy. Socialist government is a form of government in which the means of production are owned by the government of the country.
Social systems in this form of government is the one which is divided in the market and the non market forms. The means of transportation is controlled by the government here.
I would say a civil war or uprising.