What is the highest athurity in the United States

What challenges did michelangelo face when he was painting the ceiling of the sistine chapel

Which feature of government does montesquieu argue for in his book de l’esprit des lois (spirit of laws)?

The 20th amendment, also called the lame duck amendment, decreased the amount of time between the presidential election and the inaugration of the new president. what are the advancements that allowed for this amendment?