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: "the highest levels of acid precipitation in europe are in?" whose answer is Poland northward into Scandinavia.
Each document should contain about 30 words, and these documents should contain useful information.

Query: highest levels of acid precipitation in europe
Useful Output:

Doc 1: Acid rain went from being a pollution disaster to an environmental success story. How did scientists manage to prove that acid rain existed, and find a way to
Doc 2: Acidification problems are serious in many areas of North America and western Europe, where an estimated 5 to 10 million sq km acid; although
Doc 3: European countries also recorded acidic to slightly acidic pH of rainwater ranging from 4.19 to 5.82 over two decades (Keresztesi et al. 2019).
Doc 4: The pH values of precipitation in Europe ranged from 4.19 to 5.82, with an average value of 4.80. The occurrence of such low pH values can be
Doc 5: For some time, particularly during the 1980s, acid rain was by many considered to be one of the largest environmental threats of the time.