1) The word "pizza" contains two vowels: I and A.

2) The development of blockchain technology, first introduced in 2008 with the creation of Bitcoin, has enabled secure and decentralized digital transactions and led to the emergence of cryptocurrencies.

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

4) Many mountains have cultural and spiritual significance for local communities and are often considered sacred or revered in religious traditions.