China’s government has been trying all measures to reduce pollution in the past few years.

China’s government has been trying all measures to reduce pollution in the past few years. Now people can enjoy a fresh environment everywhere. The following two graphs are adopted from the column of “City Information” on the webpage of Beijing Review.
Graph 1: Olympic Cities Air Quality Report
City
Date
API
Major
Pollutant
Air Quality
Degree
Quality
Condition
Beijing
Sep 8
37
N/A
Ⅰ
Very good
Qinhuangdao
Sep 8
52
PM10
Ⅱ
Good
Qingdao
Sep 8
68
PM10
Ⅱ
Good
Shanghai
Sep 8
67
PM10
Ⅱ
Good
Shenyang
Sep 8
88
PM10
Ⅱ
Good
Tianjin
Sep 8
54
PM10
Ⅱ
Good

Graph 2: Chinese National Standard
API Values
Levels of health concern
Colors
When the API is in this range:
...air quality conditions are:
...as symbolized by this color:
0 to 50
Very good
Blue
51 to 100
Good
Green
101 to 150
Slight pollution
Yellow
151 to 200
Moderate pollution
Orange
201 to 250
Medium pollution
Red
251 to 300
High pollution
Purple
301 to 500
Hazardous
Brown
Notes:
**API stands for Air Pollution Index(指数).
**Particulate matter (PM10) is a major component of air pollution that threatens both our health and our environment. It consists of very small liquid and solid particles floating in the air.
**Sulfur dioxide(SO2) acts as an acid．Inhalation(吸入) results in labored breathing, coughing, or a sore throat and may cause permanent lung damage.
【小题1】According to Graph 1, which of the following cities has the worst air pollution?A．Qinhuangdao.B．Tianjin.C．QingdaoD．Shenyang. .【小题2】 If your city is symbolized by either red or purple, the pollution in your city is .A．Moderate or high.B．Moderate or slightC．Medium or high.D．Medium or slight. 【小题3】Which of the following statements is TURE?A．With API value below 150 the air is free from being polluted.B．The colors from purple to Yellow indicate the air quality is becoming much worse.C．When there are floating solid particles and dust in the air, it is dangerous pollution.D．On September 8th the color-symbol of Beijing City’s air quality is ‘Blue’.【小题4】When more citizens are beginning to have labored breathing soon after they are in the open air, it suggests that .A．there is a large amount of sulfur dioxide in the airB．it is so cold that they may have caught a coldC．they are starting to cough or have a feverD．they must be infected with permanent lung diseaseD

(答案→)D 解析：可联系答.案.网客服索取。

这个解释是对的