In what context does 'Panahi' and 'Upanah' mention in the medieval Indian History?

The term 'Chakla' has been used in Medieval Indian History sources. This was

In medieval India, the process of indigo extraction underwent great improvement as a result of the :

The medieval Indian writer who refers to the discovery of America is

In Indian history, who was Abdul Hamid Lahori?

In medieval India, why was the mansabdari system introduced?