Q:Answer the following question given this paragraph: Ozone near the ground harms human health. Ground-level ozone is a pollutant. But the ozone layer in the stratosphere protects us from harmful solar rays. That's why people were alarmed in the 1980s to learn that there was a hole in the ozone layer. Q: When did we learn there was a hole in the ozone layer? Choices: - 1950s - 1970s - 1990's - 1980s A:
A:
1980s