Who broke the power of 'Chahalgani' nobles?

Who among the following opposed the power of the Khalifa?

Who among the following Sultans succeeded in finally breaking and destroying the power of Turkan-i-Chihalgani?

Who was the author of Tabaqat-i-Nasiri?

Who became the Sultan of Delhi after the death of Balban?

Who was the first ruler of the Slave Dynasty?