Thank you Mohammad Ayoub, but i was much concerned to know if anyone conducted an experiment and have estimated the time spent at each phase of mitosis?
Here is answer for your question from Stanford. They used a double thymidine block to Synchronize Hela cells at the begining of S phase. Upon removal of block, cells enter to S phase at 0-4 h, entered G2 phase (5-6hrs), underwent a synchronous mitosis at 7-8 hrs, and reentered S phase after completing one full cell cycle at 14-16 hrs. Link is below if you want a closer look.