किस प्राचीन भारतीय ग्रंथ के अनुसार पत्नी को पति का आधा भाग माना गया है जो अकेले ही उसे पूर्ण करती है?

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?