How did the plantation system change after the civil war

During Reconstruction, many small white farmers, thrown into poverty by the war, entered into cotton production, a major change from prewar days when they concentrated on growing food for their own families. Out of the conflicts on the plantations, new systems of labor slowly emerged to take the place of slavery.

the answer is because he is black and completly stupid.

the answer is: must pay taxes on profits

since it is considered as a part of your income, profits from investments is eligible for tax payment.

the tax from your investment could be influenced by how long you decided to sell it. united states promotes keeping your investment for long term period. so, the tax rate for investments that you sell in less than one year is typically higher compared to investments that you sell in more than one year period.