Question: What is the hardest natural substance on Earth?

• Ans: Diamond is the hardest natural substance on Earth

Question: Who invented the telephone?

• Ans: The telephone was invented by Alexander Graham Bell

Question: Which is the largest desert in the world?

• Ans: The Sahara Desert is the largest in the world.

Question: What is the currency of the United Kingdom?

• Ans: The currency of the United Kingdom is the British Pound (GBP)

Question: What is the chemical formula for water?

• Ans: The chemical formula for water is H₂O