पुरातत्वविदों को सिंधु घाटी सभ्यता के किस स्थल पर प्रारंभिक हड़प्पा स्तरों से जुड़े एक जुते हुए खेत के साक्ष्य मिले हैं?

In Ancient Indian Statecraft, Kautilya's 'Rajamandala' theory primarily deals with:

The First Buddhist Council was held at ______.

Which ancient Indian text contains references indicating that population counts or census-like records were maintained in ancient India?