Isabella saw a chart that showed changes in the population over the past 500 years. She was surprised that the growth dramatically increased in the last 300 years. What was the reason for the increase in population since the 1700s?

People must make changes to ensure that future generations have access to natural resources. People must maintain the natural resources we have at a certain quality for a certain period of time. What is the practice of maintaining resources called?

Harry lives in a city, and he has a lung condition known as asthma. On certain days, Harry has to stay inside because pollutants in the air make it difficult for him to breathe. Which of these pollution sources are nonpoint sources that might bother Harry if he goes outside? Choose the two that apply.

Sierra lives in a southwestern town in a valley where air pollutants sometimes settle. The mountains that surround the town keep air pollution from blowing away. Sometimes Sierra can actually see the pollution in the air. Which choice is NOT a source of outdoor air pollution?

If you have ever noticed a sharp odor in the air after a thunderstorm, you might be smelling ozone. Ozone can be formed from oxygen gas when lightning passes through the air. Which statement is true about ozone?

In an area that has high air pollution, you might have seen stone buildings that are damaged, stone statues that are worn down, or cracks in the asphalt in a driveway. Or maybe you see plants that are dying for no apparent reason. You might be observing the effects of acid precipitation. Which types of gases most commonly combine with water to form acid precipitation?

Carmen lives on a farm in an area far away from the city and surrounded by forests. New families are starting to move into the area, and several of them are also farmers. Which form of land use is probably least important to Carmen and her family?

Lynne is digging a hole in which she plans to plant a tree in her yard. The last soil she dug was damp and contained lots of dead bugs and just a few rock fragments. From which soil layer was this soil dug?

Charlie lives in a small town near a wetland. Currently, a company is trying to build a factory in the wetland area, but the community is against destroying the wetland. What might be their major concerns? Choose the three statements that apply.

Forests provide a habitat for many organisms. In addition, they reduce the amount of carbon dioxide in the atmosphere and produce oxygen. What does it mean to say that forests must not only be managed, but they must be managed in a sustainable way?

The amount of Earth covered by water might imply that all water is a renewable resource. Which statement best explains why not all water is renewable?

Ja’ron lives near a river that flows through farmland. He notices that the river has become more polluted over the years. The water that was once clear is now sometimes cloudy and has an unpleasant odor. What is the most likely cause of the pollution in the river?

Henderson Island, once unaffected by humans, is located in an area where ocean pollution collects. It is estimated that the beaches of this small island are now covered with 38 million pieces of trash. Which statement best explains one likely way all this trash affects animals on or near the island?

Roberto plans on becoming a marine biologist, and he is quite concerned about cleaning up current water pollution and preventing future pollution. Which of these ways probably will be effective in reducing water pollution? Choose the three statements that apply.

A river, such as the one in the diagram, receives pollution from all the different sources shown. The types of pollutants and the amounts that enter the river will be different, but all the sources contribute to pollution of this freshwater. Examine the diagram. Which sources of pollution are point sources?

After viewing the graph of World Population Growth, Chen notices a change that happened over the past few decades. She knows there is a reason for this change. What is this kind of change called?

Jamarr moved to a new home with his family in an area that had been cleared for the subdivision. More ground is being cleared for a supermarket and other stores. He understands the need for new homes, but he also realizes that human activity has an impact on the land and its resources. Which human activities negatively affect the environment? Choose the three that apply.

Lucy reads some interesting facts about populations and their growth. She understands that a growing population has needs, including space, fresh water, and sufficient food. She learns that around 1.8 billion people in the world are ages 10 to 24, which is a large population of young people. She also reads that 52% of the total world’s population is under 30 years of age. What possible consequence can come of a continually growing population?

Scott and his family recently moved to a large city, where the air sometimes looks hazy from smog. These four steps could result in the formation of this smog:

Ozone forms.

Polluting gases react with sunlight.

Temperature inversion traps pollution.

Cars emit hydrocarbons and nitrogen oxides.

Which answer shows the order in which these steps occur?

A company understands that it has a responsibility to minimize air pollution from its factories. What are effective ways the company can reduce the pollutants produced by the factories? Choose the three statements that apply.

Jackie lives in a newly-built housing development. Which statement best explains why most of the residents are having problems with insects and mice in their homes?

We usually only hear about major oil spills. But smaller oil releases occur regularly in United States waters. They can cause damage to water organisms. Which of the following statements best summarizes the information provided by the graph?