Answer:
The new domestic slave trade helped increase the productivity of the plantation system by offering more slaves to work.
The best answer is the first one „interest enables them to control the economy”. With a higher interest rate, the lower demand of money exists, and viceversa. Besides, the interest rate is the main objective of a monetary policy which leads the economy as well.
The extension of slavery into the western territories.
For a specific instance, see the landmark supreme court case Dred Scott v. Sandford.
50 is your correct answer
