After Muhammad died who became a caliph

Explanation:

The first Caliph, Abu Bakr. By the time of Muhammad’s death in 632, I

The second Caliph Omar. Under the second caliph Omar or Hadrat Umar Farooq (634 – 644)  

The third Caliph Othman and division.

The fourth Caliph Ali and the Shiites.

i discarded the supernatant and kept the pellet in this part of the experiment because you have to return all unused chemicals into their original containers at the end of each labratory.

explanation:

option d is correct. corroborated sources of historical evidence   is necessary to validate a claim about an event in history.

historians tend to use written sources, but audio and visual materials as well as artifacts are important objects that supply information to modern historians.

historical sources are usually divided into two categories: primary and secondary sources. depending on the historian's intent, some sources shift their designation. determining what type of sources toimplement, and the level of credibility and reliability of those sources, is a significant step in critical thinking for the historian.

explanation: