Answer: B. A secondary pollutant
An acid rain is an example of a secondary pollutant because it is a chemical reaction of two gases namely, the sulfur dioxide and the nitrogen dioxide. The acid rain is not also directly emitted by the atmosphere.
Answer:
though many may argue that cake batter is a homogeneous mixture because of its observable uniformity, we know it is heterogeneous. ... In other words, the mixture of ingredients from cake batter results in some chemical reactions here and there, but we are still left with a mixture of things that can be separated.
Explanation: