Why do historians call the civil war the last of the old time wars and the first of the modern ones?

Which is the best example of a primary source ducument useful in the study of history ?

Although the three-fifths compromise northern and southern states reach an agreement that allowed for ratification of the constitution, in the long run it had a negative effect on the nation because a) it gave too much power to the executive branch of the government. b) it forced the founding fathers to add the bill of rights to the constitution. c) it was only a temporary solution to the argument between "free" and "slave" states. d) it gave too much power to state governments and not enough to the federal government.

The divide and rule policy employed by the english was developed by the