Why did Kramer call the development of writing “Sumer's most significant contribution to civilization”?

very positive impact on our industries in the west, sine they promoted settlement and increased the ways in which goods could be transported to market.  

would be the one having to do with paine talking about how the colonies are so "close" to independence anyway, since he viewed that only rational next step at this point being revolution.

your answer is indifference good luck on the test : )