What is the primary concern or issue that Web 3.0 technologies are attempting to solve?

Based on your own knowledge and research, answer the following prompts:What is the primary concern or issue that Web 3.0 technologies are attempting to solve? Why is this a problem?What is blockchain and how does it contribute to Web 3.0 goals?What are cryptocurrencies? What are their pros and cons? How do they contribute to Web 3.0 goals?