Fitna that was prevalent during the caliphate of Sayyadina Uthman (Radiyallahu Anhu)

Q: I would like to know about the fitna that was prevalent during the caliphate of sayyadina uthman (r.a) which led to his martydom and after that the battles which took place between hazrat ayesha (r.a) and saayadina ali (r.a) and with hazrat mawiya (r.a) too!!! Also what happened later which led to the incident of karbala and how did the incident of karbala end! Please provide me a broad detail about this?

Yahya (Alayhis Salaam)

Q: 

  1. How was prophet yahya martyred and what was his age at that time?
  2. What was prophet Isa's age when prophet yahya was martyred?
  3. Where was prophet zachariah when yahya was martyred?
  4. Where was maryam a.s. When prophet yahya was martyred?

Was there a prophet between prophet Jesus and Prophet Muhammad (Sallallahu Alayhi Wasallam)

Q: Was there a prophet between prophet jesus and prophet Muhammad (Sallallahu Alayhi Wasallam). Then where was prophet yehya p.b.u.h.? Was he during prophet jesus p.b.u.h.? Because prophet yehya p.b.u.h was a son prophet zakariya p.b.u.h. who was present in the same time as maryam alaihis salaam.