Population Growth and Environmental Impact

The video tutorial covers various mathematical problems related to environmental science. It starts with calculating the waste heat produced by a natural gas power plant, followed by determining the developed and untouched land areas. The tutorial then explains how to calculate percent changes in cyanide levels and SO2 emissions. Finally, it discusses population growth using the rule of 70 to determine doubling time.

If a natural gas power plant is 60% efficient and produces 1200 BTUs of electricity, how much waste heat is generated?

• 800 BTUs

• 1200 BTUs

• 1000 BTUs

• 2000 BTUs

A natural area is 35% developed, leaving 520 acres untouched. What is the total area of the land?

• 1200 acres

• 800 acres

• 1500 acres

• 1000 acres

If cyanide levels in a stream increase from 240 ppm to 360 ppm, what is the percent increase?

• 100%

• 25%

• 75%

• 50%

SO2 emissions from a coal power plant decreased from 400 tons to 288 tons. What is the percent decrease?

• 22%

• 25%

• 28%

• 30%

What is the average annual percent decrease in SO2 emissions if they declined by 28% over 7 years?

• 4%

• 2%

• 3%

• 5%

How is the growth rate calculated using births, deaths, immigrants, and emigrants?

• Births plus deaths divided by total population

• Immigrants minus emigrants divided by total population

• Births minus deaths divided by total population

• Births plus immigrants minus deaths plus emigrants divided by total population

Using the rule of 70, how many years will it take for a population with a 1% growth rate to double?

• 35 years

• 100 years

• 50 years

• 70 years

If a city's population doubles in 20 years, what is the growth rate using the rule of 70?

• 3.5%

• 2%

• 7%

• 5%

A city with a 7% growth rate will reach 60,000 people in how many years?

• 10 years

• 15 years

• 20 years

• 25 years

Which region is likely to have a population doubling in 20 years, Sub-Saharan Africa or Europe?

• Sub-Saharan Africa

• Europe

• Both

• Neither