Problem: What is the question to: "According to the World Health Organization (WHO), the United States spent more on health care per capita ($7,146), and more on health care as percentage of its GDP (15.2%), than any other nation in 2008."? The topic is Health care in the United States.

A: "how much does united states spend on health care?"


Problem: What is the question to: "The Geothermal energy of the Earth's crust originates from the original formation of the planet (20%) and from radioactive decay of minerals (80%)."? The topic is Geothermal energy.

A: "what is the source of geothermal energy?"


Problem: What is the question to: "An otoacoustic emission (OAE) is a sound which is generated from within the inner ear ."? The topic is Otoacoustic emission.

A: "what is evoked otoacoustic emissions?"


Problem: What is the question to: "At the turn of the 21st century, the expanding domain of economics in the social sciences has been described as economic imperialism ."? The topic is Economics.

A:
"What is an economic feature??"