What do these two changes have in common? acid rain weathering a marble statue
burning a marshmallow over a campfire

What is the difference between bacterial infections and viral infections?

What are the formed elements (cell or parts of cell) in blood and what are their functions ?

Match the pollutants. 1. a chlorofluorocarbon smoke 2. a biodegradable organophosphate insecticide freon 3. particle pollution paint 4. hazardous waste monoxide 5. carbon is completely burned malathion 6. carbon is incompletely burned dioxide