Greeks, Kushanas & Shakas had entered India through the North West side. Accepting the local religion would provide them the easiest way to achieve legitimacy of their rule. Since Buddhism was prevalent in the area at that time and it was provided easiest entry (Hinduism had st5rict caste based structure) so, they embraces Buddhism.
The third Sangam was held at the present Madurai in Tamil Nadu. The third sangam had 449 poets and the important ones among them include Nakkirar, Iraiyanar, Kapilar, Paranar, Sattanar, Auvikyar etc.
Third statement is incorrect because the book was originally written in Sanskrit. Arthashastra was intended as a guidebook for the king, to help him control both the people in his kingdom and the surrounding states. The Arthashastra fundamental assumption was that the king wanted to remain in power and should do whatever it took to retain it. Within the kingdom, Kautilya advocated a strict and authoritarian government aided by an extensive network of spies to gather intelligence and assess the popular mood. Although the Arthashastra was never the “Bible” of any ruling Indian dynasty, it detailed political philosophy and practices that existed in ancient and medieval India and can even be discerned in contemporary parliamentary politics.