The "Era of good feelings", was noted for the:

exceptioanlly strong leadership by monroe as head of his party.

In the 1803 case of marbury v. madison, the supreme court ruled that:

an act of congress had exceeded its constitutional authoirty
or
the executive branck must comply with an order of the court

why was the importation of slavery banned in 1808?
A. popular support for th measure casued congress to ban it
B. the fear of adding more rebellious slaves to the south
C. the 13th amendment was added to the constitution
D. it was constitutionally required as the 20 year moratorium expired.

is it A

Yes, A is correct.