With reference to the difference between the Rig Vedic and Later Vedic periods, consider the following statements

1. Only voluntary offerings were taken in the Rig Vedic Period whereas the system for Collection of taxes was established in the Later Vedic Period.

2. In the Early Vedic Period, the barter system was more prevalent whereas it was largely replaced by the exchange of gold and silver coins in the later Vedic period.

3. The Kings in Rig Vedic time did not possess any standing army but its presence was heavily seen in later Vedic times for territorial expansion.

How many of the above statements are correct?