You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "when did congress pass the clean air act?" whose answer is December 17, 1963.
Each document should contain about 30 words, and these documents should contain useful information.

Query: when did congress pass the clean air act
Useful Output:

Doc 1: Two decades later, the Clean Air Act Amendments of 1990 were passed, again with large bipartisan majorities in both houses of Congress, and
Doc 2: The Clean Air Act was passed in 1970, tightening regulations in 1977 and making further amendments in 1990.
Doc 3: The 1970 Clean Air Act is arguably Congress' most important environmental enactment. Since it became law fifty years ago, much could be and
Doc 4: Congress passed the first Clean Air Act in 1963, creating a research and regulatory programme in the US Public Health Service. The Act authorised development
Doc 5: In 1970, the United States created the Environmental Protection Agency and passed the Clean Air Act. The act originally empowered the EPA to