In what ways were the major phenomena of the first half of the twentieth-century world wars, communist revolutions, the Great Depression, fascism, the Holocaust, the emergence of the United States as global power-rooted in earlier times?

In the face of all these events of the century, the United States remained intelligent, providing weapons in the war, another making allies to remain victorious. Among all these moments in history, the United States remained one step ahead in strategic terms, of what could happen next and how to make the error something that could benefit it. In this sense, I believe that all events have made the United States become a world power through strategic acts.

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.