challenge: What is the total area of Dunbar, Nebraska, according to the United States Census Bureau?
  
  A. 1.00 square mile (2.60 km2)
  B. 0.10 square miles (0.26 km2)
  C. 0.50 square miles (1.30 km2)
  D. 0.23 square miles (0.60 km2)
  Answer: 