Problem 19
Why is a liner placed at the bottom of the landfill?
Problem 21
Compare and contrast farming and developing land. How do these activities affect stream discharge?
Problem 22
Why have natural preserves been established in the United States and in other countries?
Problem 22
Research Find out whether your community excludes yard waste from landfills.
Problem 23
What is organic farming? How is it different from conventional farming?
Problem 24
Why have some communities preserved unpaved areas where rainwater can soak into the ground?
Problem 25
Are there any disadvantages to recycling? Explain.
Problem 25
Junk Mail Collect your family's junk mail for one week and weigh it. Divide this weight by the number of people in your home. Multiply this number by 300 million (the U.S. population). If 17 trees are cut to make each metric ton of paper, calculate how many trees are cut each year to make junk mail for the entire U.S. population.
Problem 26
Why is human population growth currently called a population explosion?
Problem 26
Interpret Scientific Illustrations One hectare, shown here, is a square of land measuring 100 meters by 100 meters. How many hectares are in \(50,000 \mathrm{~m}^{2}\) of land?
