Which Christmas-themed ballet premiered in Russia in 1892?

The Nutcracker

What animal feeds its young high-fat milk to rapidly increase pup weight early in life? Which animal's teeth never stop growing, making it chew constantly? What was the U.S. naval base established in Cuba under the Platt Amendment of 1901? Which ancient structure was built predominantly from stones transported from Wales? Who was the Egyptian god with a jackal's head associated with entry to the afterlife?