TOEFL Mock Test 84: Reading Passages

Please wait...
Question 1 / 5
🏆 Rank #-- ▾
Score 0/100

1. The word "combustion" in the passage is closest in meaning to

Submit
Please wait...
About This Quiz
TOEFL Mock Test 84: Reading Passages - Quiz

Read the passage below and choose the best answers for the following questions.

2.

What first name or nickname would you like us to use?

You may optionally provide this to label your report, leaderboard, or certificate.

2. The word "periodically" in the passage is closest in meaning to

Submit

3.   POLLUTANTS (1) There are different pollutants that are dispersed throughout the world's atmosphere. According to findings, there concentrations are high enough that gradually cause serious health problems.  Serious illnesses can come quickly when air pollutants are concentrated, such as when massive injections of sulfur dioxide and suspended particulate matter are emitted by a large volcanic eruption.   (2) Carbon dioxide (CO2) is one of the major pollutants in the atmosphere. Major sources of CO2 are fossil fuels burning and deforestation. CO2 is a good transmitter of sunlight, but partially restricts infrared radiation going back from the earth into space. This produces the so-called greenhouse effect that prevents a drastic cooling of the Earth during the night. Increasing the amount of CO2 in the atmosphere reinforces this effect and is expected to result in a warming of the earth's surface. Currently, carbon dioxide is responsible for 57% of global warming trend. Nitrogen oxides contribute most of the atmospheric contaminants.   (3) Sulfur and chlorofloucarbons or CFCs are lowering the average concentration of ozone in the stratosphere too. Sulfur dioxide is produced by combustion of sulfur-containing fuels, such as coal and fuel oils. They also contribute in the process of producing sulfuric and in metallurgical process involving ores that contain sulfur. Sulfur oxides can injure man, plants and materials. At sufficiently high concentrations, sulfur dioxide irritates the upper respiratory tract of human beings because potential effect of sulfur dioxide is to make breathing more difficult by causing the finer air tubes of the lung to constrict.     (4) Chlorofluorocarbons, also known as Freons, are greenhouse gases that contribute to global warming. Photochemical air pollution is commonly referred to, as "smog". Smog, a contraction of the words smoke and fog, has been caused throughout recorded history by water condensing on smoke particles, usually from burning coal. This smog is also appearing in regions of the tropics and subtropics where savanna grasses are periodically burned.  Question:     The word "concentrated" in the passage is closest in meaning to 

Submit

4.  Which of the following best expresses the essential information in the highlighted passage?

Submit
×
Saved
Thank you for your feedback!
View My Results
Cancel
  • All
    All (4)
  • Unanswered
    Unanswered ()
  • Answered
    Answered ()
The word "combustion" in the passage is closest in meaning to
The word "periodically" in the passage is closest in meaning to
  POLLUTANTS...
 Which of the following best expresses the essential information...
play-Mute sad happy unanswered_answer up-hover down-hover success oval cancel Check box square blue
Alert!