title: First usable host address range
body: <p>I'm confused with this, I have a class A ip address which is 10.0.0.0 /8 that would require 2000 subnets, 2n^11 = 2048.. so my network prefix would be /19 and subnet mask would be 255.255.224.0.</p>
  
  <p>My question is this, If given the question "What is the usable address range of first subnet?" 
  What could be my first subnet?</p>
  
  <p>10.0.0.0 or 10.0.32.0 ?</p>
  
  <p>Sorry for my english. Cheers!</p>