How much do you know about the environment and the way we affect it? Choose the best option to each sentence below and then check the correct answers reading the text that follows it.

DID YOU KNOW?

• For every chlorofluorocarbon (CFC) molecule that's prevented from entering the atmosphere, 100,000 molecules of the ozone layer may be spared.

• It takes approximately 179 kg of coal to keep a single 100-watt incandescent light bulb burning for 12 hours each day for one year. Burning the coal to produce the energy to light the bulb creates about 425 kg of acid rain.

• For every 1 percent decrease in the earth's ozone layer there is a 2 percent increase in the incidence of skin cancer in humans.

• If one person used his own ceramic mug in the office each day, he could eliminate as many as 500 throwaway cups a year.

• Microelectronic sensors that measure sunlight and sense people entering and leaving rooms (switching on restroom lights only when somebody walks in the door) can cut energy use for lights by 50 percent.

• A single office worker using a half page cover sheet for a fax instead of a full page and sending five faxes a day would save about six rolls of paper each year.

• Each recycled beverage can will save the energy equivalent of six ounces of gasoline.

• Many of England's cities are ringed by greenbelts intended to protect farmland and prevent urban sprawl. Paris, a city for nearly 2,000 years, has planned and regulated land use since the Middle Ages.

• Almost half of Australia's surviving mammals face extinction, and 40 percent of the mammals in France, Germany, the Netherlands and Portugal are repotedly threatened as well.

• Wasting water contributes to the greenhouse effect because of the energy it takes to pump, purify and treat that water in the first place. In fact, about 2.7 kg of CO2 are emitted for every 1,000 gallons of water we use.

• Even during a mild winter, people lose significant energy through a single-pane window. In fact, the window will lose enough energy to power a 75-watt light bulb seven hours a day, 365 days a year. Using a double-pane window retains twice as much heat as a single-pane window.

• By installing low-flow aerators, a 100-employee company could save up to 25 percent of the water it uses - about 10,000 gallons annually.

• The ink printers use 99 percent less energy than laser printers while printing, and 87 percent less energy when standing by.

• Aluminium, glass and steel can be recycled almost indefinitely.

• Recycling one ton of office paper saves 17 trees. It takes 60 percent less energy to manufactures paper from recycled stock thatn from virgin materials. Making paper from recycled paper stock uses 15 percent less water than making paper 'from scratch'; recycling one ton of paper saves 7,000 gallons of water.

• A properly tuned car gets about 40 percent better gas mileage, emits 42 percent fewer hydrocarbons and 47 percent less carbon monoxide than an untuned car.

• If employees in a typical 50-person office used both sides of the paper only 10 percent of the time, the company could save 10 trees and $750 a year just in reduced paper costs.

• In New York City, each person can generate 1.8 kg of garbage daily. In Calcutta, India, a single individual produces 5 kg a day.

• Substituting a compact fluorescent for a traditional incandescent light bulb saves about one barrel of oil or 318 kg of coal. A compact fluorescent would also eliiminate over 900 kg of carbon dioxide and 6.4 kg of sulfur dioxide that are emitted into the atmosphere by a single incandescent bulg duting its lifetime.

• Commuting by public transportation takes as little as 1/13 the energy needed to commute by car.

from Newsweek