By now you should have noticed that trade becomes important to people as they settle down and develop more complex societies. What advantages does a society gain when it engages in trade?

your list doesn't mention any of them at all.

and what does "these" mean anyway ?

1) union forces launched a surprise attack.

2) more confederate troops arrived by train.

3) union forces retreated.

powers  are  denied  to the  national governmentin three distinct ways: some  powers, such as the  power  to levy duties on exports or prohibit the freedom of religion, speech, press, or assembly, are expressly  denied  to the  national government  in the  constitution.