Problem: What 1986 disaster caused pollution across Europe by the radioactive isotope caesium-137, which at least 25 years later still required livestock to be scanned on some UK upland farms?
Answer: chernobyl

Problem: The Indian astronomer Brahmagupta who lived in the 7th century is credited with introducing what fundamental mathematical concept?
Answer: number zero

Problem: Brazilian football legend Pele always wore which number
Answer: ten

Problem: Which king of England married Isabella of France?
Answer:
edward ii