Traditional Culture Encyclopedia - Weather inquiry - (20 13? Xuzhou) In recent autumn and winter, the "smog" weather in the northern cities (pictured) frequently struck. We put the diameter in the atmosphere less than or equal to 2.

(20 13? Xuzhou) In recent autumn and winter, the "smog" weather in the northern cities (pictured) frequently struck. We put the diameter in the atmosphere less than or equal to 2.

(1) The purpose of this experiment is to explore whether the concentration of PM2.5 in the air is related to the traffic volume, but the traffic volume varies at different times. So the variable of this experiment is the traffic volume.

(2) As can be seen from the statistical results in the above table, the concentration of PM2.5 in the air is the highest after work.

(3) Taking the average value of the data can reduce the experimental error. According to the data in the table, the traffic flow is the least in the early morning, and the average value of PM2.5 is 20.33. The traffic volume is the largest during working hours, with an average of 86 PM2.5; At noon, the traffic volume is small, and the average value of PM2.5 is 40.67. The traffic volume is the largest during off-duty hours, and the average value of PM2.5 is 90, which can be expressed in the form of histogram as follows:

(4) According to the analysis data, PM2.5 mainly harms human respiratory system. When air enters the lungs, it passes through the nasal cavity, pharynx, larynx, trachea and bronchus. PM2.5 particles are tiny and not easily blocked by organs such as nose, but they can directly enter bronchi and alveoli, affecting the gas exchange in the lungs and causing respiratory diseases such as asthma.

(5) According to the experimental conclusion, driving less, controlling the waste gas emitted by factories and planting more trees can improve the air quality.

So the answer is: (1) traffic flow; (2) The second half is the largest; (3) Through data processing, it can be expressed in the form of histogram as follows:

(4) respiratory system; (5) Deal with the waste gas discharged from factories and plant more trees.