What caused the split between the sunnis and shiites?

The reason behide the split between the sunnis and shiites was when Prophet Muhammad passed away. the shiites believe that after the death of Prophet Muhammad, the reign of imams started. imams were from the prophet's  household. the first imam which the shiites believe was Ali who was the cousin of Prophet Muhammad. on the other hand, sunnis. sunnis claim to believe that after the death of prophet muhammad, the reign of caliph started. sunnis believe that the first caliph was Abu Bakr who was a companion of Prophet Muhammad. 

hi there!

question - in the 1900s there were two competing views about the environment that often pitted industrialist and conservationist against one another. how were these two competing views demonstrated by the environmental policies of president roosevelt and president taft?

theodore had a quicked tempered personality while president taft was shy and barely noticable.theodore had started a dealing service with big companies which president taft completed.both were into making sure workers were always safe.president taft took the presidency more serious than theodore did.both loved to save nature.

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