Will the air be clean enough to breathe? Looking at y your answers for the last 2 questions: What is needed to cause an increase in secondary pollutants? Sunlight Wind Rain Mountains

## Step 1<br />The problem is asking us to identify the factor that can cause an increase in secondary pollutants. Secondary pollutants are not directly emitted but form when primary pollutants react with other substances in the atmosphere. <br /><br />## Step 2<br />The options provided are Sunlight, Wind, Rain, and Mountains. Among these, Sunlight is the most likely to cause an increase in secondary pollutants. This is because sunlight provides the energy necessary for chemical reactions to occur, which can lead to the formation of secondary pollutants.<br /><br />## Step 3<br />For example, sunlight can cause the reaction of nitrogen oxides with volatile organic compounds in the atmosphere to form smog, a type of secondary pollutant. <br /><br />## Step 4<br />Wind, Rain, and Mountains do not have the same direct impact on the formation of secondary pollutants as sunlight does.