Islam after muhammad's death
1) describe what happened after muhammad's death and explain how abu bake came to power?

after muhammad's death the muslim were without a leader beacuse muhammad had not named a instructed his followers how to upon his death. ultimately, muhammad's father and law and trusted friend, abuse by elected as the caliph or successor.

2) why are abu bakr, umar, uthman and ali known as the "right guided" caliphs?

Khalifa or caliph
select/choose
(his father-in-law 'Abu Bakr') 

They're known as rightly guided because they knew the prophet well and followed in his foot steps 

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