1) The Southern Ocean surrounds Antarctica and is the coldest and least-visited ocean.

2) The tongue of a blue whale is so big that about 50 people could stand on it.

3) The Russian Revolution in 1917 resulted in the overthrow of the monarchy and the establishment of a communist government under Vladimir Lenin.

4) The concept of quantum computing explores the use of quantum mechanics principles to perform complex computations, potentially revolutionizing fields such as cryptography and optimization.