Please help I really need this done and it is past due xd WILL GIVE 10 POINTS

What is the purpose of the system of checks and balances

What new concept did the the american revolution introduce into the world

What was the main point of helen hunt jackson's book, century of dishonor? a.it showed how unfairly american settlers were treated by the us government. b.it proved that american government was not responsive to the will of the people. c.it made the point that free land was no longer available to new settlers out west. d.it outlined the poor treatment of the native americans by the government.