1) The Arctic Ocean is the smallest and shallowest ocean, located at the North Pole. It is covered by sea ice for much of the year.

2) The smallest unit of time is known as a zeptosecond, which is equal to one trillionth of one billionth of a second.

3) The world's oldest known living tree is a bristlecone pine named "Methuselah" in California, estimated to be over 4,800 years old.

4) The development of artificial intelligence (AI) has led to advancements in areas such as machine learning, natural language processing, and computer vision.