Which group of people was at the very bottom of India's caste system ?

Me i really need which of these was an accomplishment of the han dynasty? the invention of the seismograph finding a water passage to europe the invention of the ballpoint pen the invention of the abacus

Why are nation-states difficult to create?

What should the christian's stand be concerning military involvement? is there ever justification for war? can a war ever be "just"? write your answer in a paragraph of 125 words.