What is the term for the brownish haze caused by air pollution?

• Mist

• Smog

• Fog

• Cloud

What harmful substances contribute to acid rain?

• Sulfur and nitrogen oxides

• Oxygen and hydrogen

• Chlorine and fluorine

• Carbon and methane

What is the effect of acid rain on aquatic life?

• It is harmful to fish

• It makes water cleaner

• It helps fish grow

• It has no effect

Which gas is believed to contribute to global warming?

• Ozone

• Carbon dioxide

• Nitrogen

• Helium

What is a major source of carbon dioxide emissions?

• Volcanic eruptions

• Plant photosynthesis

• Burning of fossil fuels

• Ocean waves