Help please !! The decision in the excerpt held which of the following to be unconstitutional?

A. Wilmot proviso
B. The Missouri compromise
C. Ostend Manifesto
D. Marbury v. Madison

Why did china build the great wall of china?

Match each person with his contribution. aristotle socrates eratosthenes hippocrates he studied the causes of illnesses in search of cures. he created a teaching method that involved asking questions. he determined that earth was round. he educated alexander the great.

Why are nation-states difficult to create?