1) They mostly spread Islam through conquering new countries. What they did also was unite all people under a single rule and ended religious uprisings.
2) There was tensions because one faction believed that Muhammad should be succeeded by someone chosen by people, while the other faction believed that his successor should be someone from his bloodline.
There are 7,100 islands in the Philippines
Answer:
Nullify: To invalidate
Popular Sovereignty: People should be able to vote
Sectionalism: Concern for ones region
State Rights: States should hold the most political power