Hello!
<span>Europe (especially Scandinavia), United States (areas like New York), Southwest Canada, Southeast China, and Taiwan.
Things that cause it are SO2 emission by volcanoes and combustion of fossil fuels such as coal and oil. I would suspect in these areas that there are a lot of cars, power plants using coal or diesel, or manufacturing that is using
combustion on site.
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Hope this Helps! Have A Wonderful Day! :)
D. <span> Heterozygous with brown leaves
It is heterozygous because the alleles are differen. Bb have different alleles, B and b. As opposed to homozygous which have same alleles, B and B or b and b.
Since B is dominant in the gene expression, and B represents brown, the dominant trait will mask the recessive one, b, and you will have a brown leaf.
Hope this helps. </span>
