1) The sunflower is not a single flower but a cluster of small flowers arranged in a spiral pattern.

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 word "pizza" contains two vowels: I and A.

4) The world's largest diamond, the Cullinan, was discovered in South Africa in 1905 and weighed over 3,000 carats.